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We consider the optimization of a finite-time Carnot engine characterized by small dissipations. We bound the power with a simple inequality and show that the optimal strategy is to perform small cycles around a given working point, which can be, thus, chosen optimally. Remarkably, this optimal point is independent of the figure of merit combining power and efficiency that is being maximized. Furthermore, for a general class of dissipative dynamics the maximal power output becomes proportional to the heat capacity of the working substance. Since the heat capacity can scale supraextensively with the number of constituents of the engine, this enables us to design optimal many-body Carnot engines reaching maximum efficiency at finite power per constituent in the thermodynamic limit.We study inclusive and diffractive dijet production in electron-proton and electron-nucleus collisions within the color glass condensate effective field theory. We compute dijet cross sections differentially in both mean dijet transverse momentum P and recoil momentum Δ, as well as the anisotropy in the relative angle between P and Δ. Our results cover a much larger kinematic range than accessible in previous computations performed in the correlation limit approximation, where it is assumed that |P|≫|Δ|. We validate this approximation in its range of applicability and quantify its failure for |P|≲|Δ|. We also predict significant target-dependent deviations from the correlation limit approximation for |P|>|Δ| and |P|≲Q_s, which offers a straightforward test of gluon saturation and access to multigluon distributions at a future Electron-Ion Collider.We propose a time-of-arrival operator in quantum mechanics by conditioning on a quantum clock. This allows us to bypass some of the problems of previous proposals, and to obtain a Hermitian time of arrival operator whose probability distribution arises from the Born rule and which has a clear physical interpretation. The same procedure can be employed to measure the “time at which some event happens” for arbitrary events (and not just specifically for the arrival time of a particle).Chemical potential energy harvesting from the concentration gradient has been largely improved recently due to the development of nanofluidic energy conversion systems. However, the reported systems mainly focus on improving the membrane’s performance but neglect the forms of concentration gradient. Here, we demonstrate the chemical reaction assisted chemical-potential-driven directional ion transport through layered titanium carbides membranes for energy harvesting. NCT-503 nmr The MXene membrane with negatively charged nanochannels shows excellent cation selectivity and could reach 1.1 W/m2 for a 500-fold salinity gradient. By adopting the traditional neutralization reaction, HCl/KOH as the acid-base pair (ABP), the power density can reach 7.89 W/m2 with 1 M ABP due to the maintained transmembrane proton gradient. Besides, the membrane’s excellent acid-base stability renders the power density stable for ∼192 h without obvious damping. This work provides new inspiration for industrial waste treatment issues and would be worth exploring its potential applications in extreme environments.The scanning tunneling microscope-based break junction (STM-BJ) is used widely to create and characterize single metal-molecule-metal junctions. In this technique, conductance is continuously recorded as a metal point contact is broken in a solution of molecules. Conductance plateaus are seen when stable molecular junctions are formed. Typically, thousands of junctions are created and measured, yielding thousands of distinct conductance versus extension traces. However, such traces are rarely analyzed individually to recognize the types of junctions formed. Here, we present a deep learning-based method to identify molecular junctions and show that it performs better than several commonly used and recently reported techniques. We demonstrate molecular junction identification from mixed solution measurements with accuracies as high as 97%. We also apply this model to an in situ electric field-driven isomerization reaction of a [3]cumulene to follow the reaction over time. Furthermore, we demonstrate that our model can remain accurate even when a key parameter, the average junction conductance, is eliminated from the analysis, showing that our model goes beyond conventional analysis in existing methods.The GaCl3-catalyzed [4 + 2] cycloaddition between alkoxy- and aryl-activated donor-acceptor cyclobutane diesters and cis-diazene 1a (4-phenyl-1,2,4-triazoline-3,5-dione, PTAD) is disclosed. The reaction provides hexahydropyridazine derivatives as single diastereomers in good to excellent yields in most cases. The structural assignment of the cycloadduct 3b was unambiguously established by single-crystal X-ray diffraction.Methods currently available to estimate the postmortem submerged interval (PMSI) of cadavers in water suffer from poor accuracy, being mostly based on morphological examination of the remains. Proteins present within bones have recently attracted more attention from researchers interested in the estimation of the postmortem interval (PMI) in terrestrial environments. Despite the great potential of proteomic methods for PMI estimation, their application to aquatic environments has not yet been explored. In this study, we examined whether four different types of aquatic environment affected the proteome of mice bones with increasing PMSIs. Results showed that increasing PMSIs can influence the protein abundances more than the different types of water. In particular, the abundance of the muscle protein fructose-bisphosphate aldolase A constantly decreased with increasing PMSIs. Additionally, the protein peptidyl-prolyl cis-trans isomerase showed a significant decrease between controls and aquatic environments. Furthermore, the coagulation factor VII was deamidated only in submerged samples and not in terrestrial controls. Finally, fetuin-A was significantly more deamidated in pond water compared to the other aquatic environments. Overall, this study identified novel potential biomarker candidates that would be useful for the estimation of the PMSI and for the characterization of the type of water involved in criminal investigations.