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Self-healable polymer complex with a giant ionic thermoelectric effect
No full textIn this study, we develop a stretchable/self-healable polymer, PEDOT:PAAMPSA:PA, with remarkably high ionic thermoelectric (iTE) properties: an ionic figure-of-merit of 12.3 at 70% relative humidity (RH). The iTE properties of PEDOT:PAAMPSA:PA are optimized by controlling the ion carrier concentration, ion diffusion coefficient, and Eastman entropy, and high stretchability and self-healing ability are achieved based on the dynamic interactions between the components. Moreover, the iTE properties are retained under repeated mechanical stress (30 cycles of self-healing and 50 cycles of stretching). An ionic thermoelectric capacitor (ITEC) device using PEDOT:PAAMPSA:PA achieves a maximum power output and energy density of 4.59 ??W???m???2 and 1.95 mJ???m???2, respectively, at a load resistance of 10???K??, and a 9-pair ITEC module produces a voltage output of 0.37???V???K???1 with a maximum power output of 0.21 ??W???m???2 and energy density of 0.35 mJ???m???2 at 80% RH, demonstrating the potential for a self-powering source
Convection-permitting simulations reveal expanded rainfall extremes of tropical cyclones affecting South Korea due to anthropogenic warming
No full textUnderstanding how global warming affects tropical cyclone (TC) intensity and precipitation for target regions is essential to preparing for associated damages but detailed processes remain uncertain. This study provides the first quantification of anthropogenic influences on TC characteristics affecting South Korea using convection-permitting model (CPM) simulations (3 km resolution). For the observed four recent TCs that strongly affected South Korea, CPM simulations were performed under current (ALL) and counterfactual conditions without human influences (NAT). The observed sea surface temperature and lateral boundary conditions were used for ALL while changes attributable to human influences (estimated using CMIP6 multimodel simulations) were removed from observed boundary conditions for NAT runs. ALL experiments captured the observed TC intensity and precipitation reasonably. After removing human influences, TC intensity and precipitation were reduced in NAT experiments. Importantly, areas with extreme precipitation (i.e., having precipitation larger than 150 mm) were found to expand by 16-37% in ALL compared to NAT, which was induced by an enhanced upward motion near the TC core and an increase of background water vapor in line with warming. Further, the role of increased moisture was found to become important as TC moves to mid-latitudes. This study provides valuable insights into how greenhouse warming can intensify TC-induced extreme precipitation over East Asia
A Universal Strategy for Enhancing Hydrogen Production by Boosting Electrochemical Gas Evolution with Hydrogel Film
No full textLaser pulse compression by a density gradient plasma for exawatt to zettawatt lasers
No full textWe propose a new method of compressing laser pulses to ultrahigh powers based on spatially varying dispersion of an inhomogeneous plasma. Here, compression is achieved when a long, negatively frequency-chirped laser pulse reflects off the density ramp of an over-dense plasma slab. As the density increases longitudinally, high-frequency photons at the leading part of the laser pulse penetrate more deeply into the plasma region than lower-frequency photons, resulting in pulse compression in a similar way to that by a chirped mirror. Proof-of-principle simulations performed using particle-in-cell simulation codes predict compression of a 2.35 ps laser pulse to 10.3 fs-a ratio of 225. As plasma is robust and resistant to damage at high intensities-unlike solid-state gratings commonly used in chirped-pulse amplification-the method could be used as a compressor to reach exawatt or zettawatt peak powers. Researchers propose a laser pulse compression method for exawatt to zettawatt lasers based on spatially varying dispersion of an inhomogeneous plasma. This may enable, for example, pulse compression of a laser pulse from 2.35 ps to 10.3 fs. The approach is robust at high intensities
VAFOR: Proactive Voice Assistant for Object Retrieval in the Physical World
No full textIn this paper, we present a proactive robotic voice assistant with a perceive-reason-act loop that carries out pick-and-place operations based on verbal commands. Unlike existing systems, our robot can retrieve a target object not only when the target is explicitly spelled out, but also given an indirect command that implicitly reflects the human intention or emotion. For instance, when the verbal command is ???I had a busy day, so I didn???t have much to eat.???, the target object would be something that can help with hunger. To successfully estimate the target object from indirect commands, our framework consists of separate modules for the complete perceive-reason-act loop as follows. First, for perception, it runs an object detector on the robot???s onboard computer to detect all objects in the surroundings and records a verbal command from a microphone. Second, for reasoning, a list of available objects as well as a transcription of the verbal command are integrated into a prompt for a Large Language Model (LLM) in order to identify the target object in the command. Finally, for action, a TurtleBot3 with a 5 DOF robotic arm finds the target object and brings it to the human. Our experiments show that with a properly designed prompt, the robot can identify the correct target object from implicit commands with at most 97% accuracy. In addition, it is shown that the technique of fine-tuning a language model based on the proposed prompt designing process amplifies the performance of the smallest language model by a factor of five. Our data and code are available at https://github.com/bekatan/vafo
Epigenetic regulation of Neuregulin 1 promotes breast cancer progression associated to hyperglycemia
No full textHyperglycemia is a risk factor for breast cancer-related morbidity and mortality. Hyperglycemia induces
Neuregulin 1 (Nrg1) overexpression in breast cancer, which subsequently promotes tumor progression.
However, molecular mechanisms underlying hyperglycemia-induced Nrg1 overexpression remain poorly
understood. Here, we show that hyperglycemia causes active histone modifications at the Nrg1
enhancer, forming enhanceosome complexes where recombination signal binding protein for
immunoglobulin kappa J region (RBPJ), E1A binding protein p300 (P300), and SET domain containing 1A
(SETD1A) are recruited to upregulate Nrg1 expression. Deletions in RBPJ-binding sites causes
hyperglycemia-controlled Nrg1 levels to be downregulated, resulting in decreased tumor growth in vitro
and in vivo. Mice with modest-temporary hyperglycemia, induced by low-dose short-exposure
streptozotocin, display accelerated tumor growth and lapatinib resistance, whereas combining lapatinib
with N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-S42 phenylglycine t-butyl ester (DAPT) ameliorates tumor
growth under these modest hyperglycemic conditions by inhibiting NOTCH and EGFR superfamilies.
NOTCH activity is correlated with NRG1 levels, and high NRG1 levels predicts poor outcomes, particularly
in HER2-positive breast cancer patients. Our findings highlight the hyperglycemia-linked epigenetic
modulation of NRG1 as a potential therapeutic strategy for treating breast cancer patients with diabete
Fluctuating levels of Fam3c in cancer-associated adipocytes contribute to breast cancer cell survival and metastasis
No full textAdipose tissue within the tumor microenvironment (TME) plays a critical role in breast cancer progression. Here, we identified FAM3 metabolism-regulating signaling molecule C (Fam3c), produced in cancer-associated adipocytes (CAAs), as a regulator of tumor development. Fam3c overexpression in cultured adipocytes significantly decreased cell death in both the adipocytes and co-cultured cancer cells, while inhibiting fibrosis. Conversely, Fam3c depletion in CAAs underwent adipocyte-mesenchymal transition (AMT) in association to increased fibrosis in the TME. Adipocyte Fam3c expression was driven by TGF-?? signaling from breast cancer cells and was ameliorated upon treatment with a TGF-??-neutralizing antibody. Early Fam3c knockdown in CAAs in a tumorigenic mouse model led to significant inhibition of primary and metastatic tumor growth. Our results suggest that therapeutic inhibition of high levels of Fam3c in CAAs during early tumor development could be beneficial in treatment of breast cancer patient
Fluid-like elastic metasurface
No full textWhat makes elastic waves different from other waves is the existence of various wave modes and coupling between these modes. Accordingly, the manipulation of elastic waves suffers from many limitations due to mode coupling, which is an inherent complex physical property of elastic waves. In this study, we propose fluid-like elastic metasurfaces that act as an acoustic (fluid) surface to perfectly eliminate mode coupling. Because longitudinal and shear waves are decoupled, only reflected longitudinal (or shear) waves exist when longitudinal (or shear) waves are incident. Using a strip-type unit cell, elastic metasurfaces mimicking acoustic hard-wall and soft-wall were designed and realized. In addition, numerical analysis and experiments were conducted to prove the validity of the designed unit cells. This study presents a more versatile metasurface by solving the mode coupling of solid elastic waves. In addition, two types of designed fluid-like metasurfaces are expected to be utilized in further studies considering the opposite phase shift characteristic
Biomolecular condensate assembly of nArgBP2 tunes its functionality to manifest the structural plasticity of dendritic spines
No full textnArgBP2, a candidate gene for intellectual disability, is a postsynaptic protein critical for dendritic spine development and morphogenesis, and its knockdown (KD) in developing neurons severely impairs spine-bearing excitatory synapse formation. Surprisingly, nArgBP2 KD in mature neurons did not cause morphological defects in the existing spines at rest, raising questions of how it functions in mature neurons. We found that unlike its inaction at rest, nArgBP2 KD completely inhibited the enlargement of dendritic spines during chemically induced long-term potentiation (cLTP) in mature neurons. We further found that nArgBP2 forms condensates in dendritic spines and that these condensates are dispersed by cLTP, which spatiotemporally coincides with spine head enlargement. Condensates with CaMKII phosphorylation-deficient mutant or CaMKII inhibition are neither dispersed nor accompanied by spine enlargement during cLTP. We found that nArgBP2 condensates in spines exhibited liquid-like properties, and in heterologous and in vitro expression systems, nArgBP2 undergoes liquid-liquid phase separation via multivalent intermolecular interactions between SH3 domains and proline-rich domains. It also forms coacervates with CaMKII alpha, which is rapidly dissembled by calcium/CaMKII alpha-dependent phosphorylation. We further showed that the interaction between nArgBP2 and WAVE1 competes with nArgBP2 phase separation and that blocking the nArgBP2-WAVE1 interaction prevents spine enlargement during cLTP. Together, our results suggest that nArgBP2 at rest is confined to the condensates but is released by CaMKII alpha-mediated phosphorylation during synaptic plasticity, which regulates its timely interaction with WAVE1 to induce spine head enlargement in mature neurons