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The faithful storage and coherent manipulation of quantum states with matter-systems would enable the realization of large-scale quantum networks based on quantum repeaters. To achieve useful communication rates, highly multimode quantum memories are required to construct a multiplexed quantum repeater. Here, we present a demonstration of on-demand storage of orbital-angular-momentum states with weak coherent pulses at the single-photon-level in a rare-earth-ion-doped crystal. Through the combination of this spatial degree-of-freedom (DOF) with temporal and spectral degrees of freedom, we create a multiple-DOF memory with high multimode capacity. This device can serve as a quantum mode converter with high fidelity, which is a fundamental requirement for the construction of a multiplexed quantum repeater. This device further enables essentially arbitrary spectral and temporal manipulations of spatial-qutrit-encoded photonic pulses in real time. Therefore, the developed quantum memory can serve as a building block for scalable photonic quantum information processing architectures. Multiplexing of quantum memories would enable higher communication rate for repeater based quantum networks. Here, the authors demonstrate multiplexed storage of single-photon-level pulses using multiple degree-of-freedom, with the additional function of arbitrary manipulation of photonic pulses in real time.

During an immune response, macrophages undergo systematic metabolic rewiring tailored to support their functions. Branched-chain amino acid (BCAA) metabolism has been reported to modulate macrophage function; however, its role in macrophage alternative activation remain unclear. We aimed to investigate the role of BCAA metabolism in macrophage alternative activation. The metabolomics of BMDM-derived M0 and M2 macrophages were analyzed using LC-MS. BCAAs were supplemented and genes involved in BCAA catabolism were inhibited during M2 macrophage polarization. The expression of M2 marker genes was assessed through RT-qPCR, immunofluorescence, and flow cytometry. Metabolomic analysis identified increased BCAA metabolism as one of the most significantly rewired pathways upon alternative activation. M2 macrophages had significantly lower BCAA levels compared to controls. BCAA supplementation promoted M2 macrophage polarization both in vitro and in vivo and increased oxidative phosphorylation in M2 macrophages. Blocking BCAA entry into mitochondria by knockdown of SLC25A44 inhibited M2 macrophage polarization. Furthermore, M2 macrophages polarization was suppressed by knockdown of Branched-chain amino-acid transaminase 2 (BCAT2) and branched chain keto acid dehydrogenase E1 subunit alpha (BCKDHA), both of which are key enzymes involved in BCAA oxidation. Overall, our findings suggest that BCAA catabolism plays an important role in polarization toward M2 macrophages.

The transient accumulation of triglyceride (TG)‐enriched lipid droplets (LDs) in hepatocytes during early liver regeneration is critical for generation but remains mechanistically unclear, particularly the roles of LD fusion‐associated proteins in lipid mobilization. Here, through integrated lipidomic and transcriptomic analyses, Cell death‐inducing DNA fragmentation factor‐like Effector C (CIDEC), an LD‐associated protein upregulated during this phase is identified, as a negative regulator of regeneration through its unexpected role in sequestering TG within LDs. Mechanistically, CIDEC acts as a metabolic gatekeeper: its depletion after peak LD accumulation promotes TG mobilization and enhances fatty acid oxidation (FAO)‐driven regeneration. This pro‐regenerative effect is abolished by FAO inhibition, underscoring the central role of TG catabolism. Conversely, overexpression of CIDEC or the TG biosynthetic enzyme Diacylglycerol O‐acyltransferase 2 (DGAT2) exacerbates TG retention and impairs liver regeneration. Notably, CIDEC depletion significantly improves regenerative outcomes in mice with chronic steatosis. These findings reveal a previously unrecognized role for LD fusion in regulating the TG storage‐utilization balance, where its suppression promotes metabolic flexibility to meet the energetic demands of liver regeneration. This metabolic checkpoint may be targeted to overcome impaired liver regeneration associated with fatty liver disease.

Background. Luhong formula (LHF)—a traditional Chinese medicine containing Cervus nippon Temminck, Carthamus tinctorius L., Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao, Codonopsis pilosula (Franch.) Nannf., Cinnamomum cassia Presl, and Lepidium apetalum Willd—is used in the treatment of heart failure, but little is known about its mechanism of action. We have investigated the effects of LHF on antifibrosis. Methods. Forty-eight SD male rats were randomly assigned into six groups (n = 8), model group, sham-operation group, perindopril group (0.036 mg/ml), LHF high doses (LHF-H, 1.44 g/mL), LHF middle doses (LHF-M, 0.72 g/mL), and LHF low doses (LHF-L, 0.36 g/mL). Except the sham-operation group, the other groups were received an abdominal aorta constriction to establish a model of myocardial hypertrophy. The HW and LVW were measured to calculate the LVW/BW and HW/BW. ELISA was used to detect the serum concentration of BNP. The expressions of eNOS, TGF-β1, caspase-3, VEGF, and VEGFR2 in heart tissues were assessed by western blot analysis. mRNA expressions of eNOS, Col1a1, Col3a1, TGF-β1, VEGF, and VEGFR2 in heart tissues were measured by RT-PCR. The specimens were stained with hematoxylin-eosin (HE) and picrosirius red staining for observing the morphological characteristics and collagen fibers I and III of the myocardium under a light microscope. Results. LHF significantly lowered the rat’s HW/BW and LVM/BW, and the level of BNP in the LHF-treated group compared with the model group. Histopathological and pathomorphological changes of collagen fibers I and III showed that LHF inhibited myocardial fibrosis in heart failure rats. Treatment with LHF upregulated eNOS expression in heart tissue and downregulated Col1a1, Col3a1, TGF-β1, caspase-3, VEGF, and VEGFR2 expression. Conclusion. LHF can improve left ventricular remodeling in a pressure-overloaded heart failure rat model; this cardiac protective ability may be due to cardiac fibrosis and attenuated apoptosis. Upregulated eNOS expression and downregulated Col1a1, Col3a1, TGF-β1, caspase-3, VEGF, and VEGFR2 expression may play a role in the observed LHF cardioprotective effect.

Abdominal aortic aneurysm (AAA) is strongly correlated with obesity, partially due to the abnormal expansion of abdominal perivascular adipose tissue (PVAT). Cell death-inducing DNA fragmentation factor-like effector C (CIDEC), also known as fat-specific protein 27 (FSP27) in rodents, is specifically expressed in adipose tissue where it mediates lipid droplet fusion and adipose tissue expansion. Whether and how CIDEC/FSP27 plays a role in AAA pathology remains elusive. Here, we show that FSP27 exacerbates obesity and angiotensin Ⅱ (Ang Ⅱ)-induced AAA progression. FSP27 deficiency in mice inhibited high-fat diet-induced PVAT expansion and inflammation. Both global and adipose tissue-specific FSP27 ablation significantly decreased obesity-related AAA incidence. Deficiency of FSP27 in adipocytes abrogated matrix metalloproteinase-12 (MMP12) expression in aortic tissues. Infiltrated macrophages, which partially colocalize with MMP12, were significantly decreased in the FSP27-deficient aorta. Mechanistically, knockdown of Fsp27 in 3T3-L1 adipocytes inhibited C–C motif chemokine ligand 2 (CCL2) expression and secretion through a c-Jun N-terminal kinase (JNK)-dependent pathway, thereby leading to reduced induction of macrophage migration, while Cidec overexpression rescued this effect. Overall, our study demonstrates that CIDEC/FSP27 in adipose tissue contributes to obesity-related AAA formation, at least in part, by enhancing PVAT inflammation and macrophage infiltration, thus shedding light on its significance as a key regulator in the context of obesity-related AAA.

High-speed landslide is a catastrophicgeological disaster in the mountainous area ofsouthwest China. To predict the movement process oflandslide reactivation in Chenjiaba town, Beichuancounty, Sichuan province, China, we simulated themovement process of two landslide failures inChenjiaba via rapid mass movement simulation andunmanned aerial vehicle images （UAV）, and obtainedthe movement characteristic parameters of thelandslides. According to a back analysis, the mostremarkable fitting theological parameters werefriction coefficient （μ = 0.18 ） and turbulence（ ζ = 400 m. s-2 ）. The parameter of landslidepressure was applied as the zoning index of landslidehazard to obtain the influence zone and hazard zoningmap of the Chenjiaba landslide. Results show that theDuba River was blocked quickly with a landslideaccumulation at the maximum height of 44.14 mwhen the Chenjiaba deposits lost stability. The hazardzoning map indicated that the landslide hazard degreeis positively correlated with the slope. This landslideassessment is a quantitative hazard assessmentmethod based on a landslide movement process andis suitable for high-speed landslide. Such method canprovide a scientific basis for urban construction andplanning in the landslide hazard area to avoid hazardseffectively.

Praseodymium (Pr\\(^{3+}\\)) ions doped in the site 1 of yttrium orthosilicate (Y\\(_2\\)SiO\\(_5\\)) has been widely employed as the photonic quantum memory due to their excellent optical coherence and spin coherence. While praseodymium ions occupying the site 2 in Y\\(_2\\)SiO\\(_5\\) crystal have better optical coherence as compared with those at site 1, which may enable better performance in quantum memory. Here we experimentally characterize the hyperfine interactions of the ground state \\(^3\\)H\\(_4\\) and excited state \\(^1\\)D\\(_2\\) of Pr\\(^{3+}\\) at site 2 in Y\\(_2\\)SiO\\(_5\\) using Raman heterodyne detected nuclear magnetic resonance. The Hamiltonians for the hyperfine interaction are reconstructed for both ground state \\(^3\\)H\\(_4\\) and excited state \\(^1\\)D\\(_2\\) based on the Raman heterodyne spectra in 201 magnetic fields. The two-pulse spin-echo coherence lifetime for the ground state is measured to be 2.6\\(\\pm\\)0.1 ms at site 2 with zero magnetic field, which is more than five times longer than that at site 1. The magnetic fields with zero first order Zeeman shift in the hyperfine transition for Pr\\(^{3+}\\) at site 2 in Y\\(_2\\)SiO\\(_5\\) are identified.

An experimental platform of ultralow-temperature pulsed ENDOR (electron-nuclear double resonance) spectroscopy is constructed for the bulk materials. Coherent property of the coupled electron and nuclear spins of the rare-earth (RE) dopants in a crystal (143Nd3+:Y2SiO5) is investigated from 100 mK to 6 K. At the lowest working temperatures, two-pulse-echo coherence time exceeding 2 ms and 40 ms are achieved for the electron and nuclear spins, while the electronic Zeeman and hyperfine population lifetimes are more than 15 s and 10 min. With the aid of the near-unity electron spin polarization at 100 mK, the complete hyperfine level structure with 16 energy levels is measured using ENDOR technique without the assistance of the reconstructed spin Hamiltonian. These results demonstrate the suitability of the deeply cooled paramagnetic RE-doped solids for memory components aimed for quantum communication and quantum computation. The developed experimental platform is expected to be a powerful tool for paramagnetic materials from various research fields.

\\(\\mathrm {^{151}Eu^{3+}}\\)-doped yttrium silicate (\\(\\mathrm {^{151}Eu^{3+}:Y_2SiO_5}\\) ) crystal is a unique material that possesses hyperfine states with coherence time up to 6 h. Many efforts have been devoted to the development of this material as optical quantum memories based on the bulk crystals, but integrable structures (such as optical waveguides) that can promote \\(\\mathrm {^{151}Eu^{3+}:Y_2SiO_5}\\)-based quantum memories to practical applications, have not been demonstrated so far. Here we report the fabrication of type 2 waveguides in a \\(\\mathrm {^{151}Eu^{3+}:Y_2SiO_5}\\) crystal using femtosecond-laser micromachining. The resulting waveguides are compatible with single-mode fibers and have the smallest insertion loss of \\(4.95\\ dB\\). On-demand light storage is demonstrated in a waveguide by employing the spin-wave atomic frequency comb (AFC) scheme and the revival of silenced echo (ROSE) scheme. We implement a series of interference experiments based on these two schemes to characterize the storage fidelity. Interference visibility of the readout pulse is \\(0.99\\pm 0.03\\) for the spin-wave AFC scheme and \\(0.97\\pm 0.02\\) for the ROSE scheme, demonstrating the reliability of the integrated optical memory.

Macroscopic realism is a classical worldview that a macroscopic system is always determinately in one of the two or more macroscopically distinguishable states available to it, and so is never in a superposition of these states. The question of whether there is a fundamental limitation on the possibility to observe quantum phenomena at the macroscopic scale remains unclear. Here we implement a strict and simple protocol to test macroscopic realism in a light-matter interfaced system. We create a micro-macro entanglement with two macroscopically distinguishable solid-state components and rule out those theories which would deny coherent superpositions of up to 76 atomic excitations shared by 10^10 ions in two separated solids. These results provide a general method to enhance the size of superposition states of atoms by utilizing quantum memory techniques and to push the envelope of macroscopicity at higher levels.