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Pneumococcal Sepsis in a Patient with Asplenia and Hypogammaglobulinemia
Temperature-driven mechanistic transition in propylene oxidation over Pt/CeO2 ensemble catalysts
Abstract Pt/CeO2 ensemble catalysts are promising for propylene (C3H6) oxidation in vehicle exhaust, yet identifying the intrinsic active sites and understanding how the metal-support interface evolves at varying reaction temperatures remains contentious. Herein, we demonstrate that H2-activated Pt/CeO2 ensemble catalysts feature metallic Pt ensembles as intrinsic active sites, lowering the 50% conversion temperature by 120 °C after hydrogen activation. Various operando characterization techniques reveal an approximately 170 °C threshold temperature for the dynamic change of the reaction models. Meanwhile, kinetics and theoretical analysis illustrates that oxygen-facilitated dehydrogenation of sp 3 C-H bonds is the rate-determining step. At low temperatures, both C3H6 and O2 adsorb and activate on metallic Pt, without CeO2 involvement. Once the temperature exceeds threshold, C3H6 fully covers Pt sites, while O2 activates over Pt-O-Ce interfaces and participates in dehydrogenation. This study highlights the dynamic nature of oxygen activation, leading to distinct reaction temperature regimes during C3H6 oxidation.
Competency-Based Medical Education at the Front Lines of Patient Care
Pushing the boundary of quantum advantage in hard combinatorial optimization with probabilistic computers
Abstract Recent demonstrations on specialized benchmarks have reignited excitement for quantum computers, yet their advantage for real-world problems remains an open question. Here, we show that probabilistic computers, co-designed with hardware to implement Monte Carlo algorithms, provide a scalable classical pathway for solving hard optimization problems. We focus on two algorithms applied to three-dimensional spin glasses: discrete-time simulated quantum annealing and adaptive parallel tempering. We benchmark these methods against a leading quantum annealer. For simulated quantum annealing, increasing replicas improves residual energy scaling, consistent with extreme value theory. Adaptive parallel tempering, supported by non-local isoenergetic cluster moves, scales more favorably and outperforms simulated quantum annealing. Field Programmable Gate Arrays or specialized chips can implement these algorithms in modern hardware, leveraging massive parallelism to accelerate them while improving energy efficiency. Our results establish a rigorous classical baseline for assessing practical quantum advantage and present probabilistic computers as a scalable platform for real-world optimization challenges.
BCMA T-Cell Engager Therapy in Patients with Refractory Autoimmune Disease
Virus-inspired lipopeptide-derived nucleic acid delivery to cartilage for osteoarthritis therapy
Alive and Kicking
Ring expansion of bicyclo[1.1.0]butyl ketones to bicyclo[2.1.1]hexenes using ketone as both activating and reacting groups
Mass Administration of Azithromycin to Infants in Mali to Reduce Mortality
Optically-biased Rydberg microwave receiver enabled by hybrid nonlinear interferometry
Abstract Coupling a Rydberg vapour medium to both microwave and optical fields enables the benefits of all-optical detection, such as minimal disturbance of the measured field and resilience to very strong signals, since no conventional antenna is required. However, peak sensitivity typically relies on adding a microwave local oscillator, which compromises the all-optical nature of the measurement. Here we introduce an alternative, optical-bias detection, that maintains fully optical operation while achieving high sensitivity. To address laser phase noise, which is critical in this approach, we perform a simultaneous measurement of the noise using a nonlinear process and correct it in real time via data processing. This yields a 35 dB improvement in signal-to-noise ratio compared with the basic method. We demonstrate a sensitivity of $$176\,{{{\rm{nV}}}}/{{{\rm{cm}}}}/\sqrt{{{{\rm{Hz}}}}}$$ 176 nV / cm / Hz , reliable operation up to 3.5 mV/cm at 13.9 GHz, and quadrature-amplitude modulated data transmission, underlining the ability to detect microwave field quadratures while preserving the unique advantages of all-optical detection.
Advancing Surveillance of Health Care–Associated Infections — Targeting Hospital-Onset Sepsis
Thymic epithelial cells amplify epigenetic noise to promote immune tolerance
Million-year solar wind irradiation recorded in chang’E-5 and chang’E-6 samples
Abstract The long-term effects of Earth’s magnetosphere on solar wind (SW) irradiation asymmetry between the lunar nearside and farside, and their implications for space weathering processes, remain poorly characterized. Here, we measure exposure ages and SW-induced amorphous rim thicknesses of individual grains from the Chang’E-5 (CE-5) and Chang’E-6 (CE-6) lunar soils to derive rim growth rates. Comparative analysis of SW irradiation records from CE-5, CE-6, and Apollo (11, 16, 17) samples reveals that CE-6 grains from the southern mid-latitude farside exhibit higher rim growth rates than those from the low-latitude nearside Apollo sites. This trend aligns with simulated lunar surface SW fluxes and is consistent with the hypothesis that reduced SW exposure on the nearside, due to Earth’s magnetospheric shielding, may contribute to a persistent hemispheric asymmetry in SW irradiation. However, CE-5 samples from the northern mid-latitude nearside yield unexpectedly high rim growth rates, suggesting the potential involvement of additional local factors. The exact reasons for this anomaly remain unclear and warrant further investigation.