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Most caching policies focus on increasing object hit rate to improve overall system performance. However, these algorithms are insufficient for transactions. In this work, we define a new metric, transactional hit rate, to capture when caching reduces latency for transactions. We present DeToX, a caching system that leverages transactional dependencies to make eviction and prefetching decisions. DeToX is able to significantly outperform single-object alternatives on real-world workloads and popular OLTP benchmarks, providing up to a 130% increase in transaction hit rate and 3.4x improvement in cache efficiency. 

Thermoelectric properties of oxygen-deficient filled strontium barium niobates (SBN, Sr x Ba 6− x Nb 10 O 30−δ ) in the composition range from the barium end member to a Sr:Ba ratio of 80:20 were investigated. The electrical conductivity, Seebeck coefficients, and power factors for ceramic samples annealed at 1300–1310 °C for 30 h under forming gas (∼10 −16 pO 2 atm) were evaluated from ∼350 to 970 K. The conduction mechanism in the filled SBNs was found to be similar to that of the heavily-reduced unfilled SBNs reported in literature. However, relative to the unfilled counterparts heat-treated at 10 −16 atm pO 2 , larger power factors were observed in the filled SBNs. The thermoelectric performance of these filled SBNs was composition-sensitive; lower Sr contents showed higher electrical conductivities, and power factors. Electron diffraction and Hall experiments suggest that both mobility and carrier concentration are enhanced with decreasing Sr. For ceramic samples, the highest power factors achievable were found for low Sr, heavily-reduced filled compositions. 

Abstract To exploit their charge transport properties in transistors, semiconducting carbon nanotubes must be assembled into aligned arrays comprised of individualized nanotubes at optimal packing densities. However, achieving this control on the wafer‐scale is challenging. Here, solution‐based shear in substrate‐wide, confined channels is investigated to deposit continuous films of well‐aligned, individualized, semiconducting nanotubes. Polymer‐wrapped nanotubes in organic ink are forced through sub‐mm tall channels, generating shear up to 10 000 s⁻¹uniformly aligning nanotubes across substrates. The ink volume and concentration, channel height, and shear rate dependencies are elucidated. Optimized conditions enable alignment within a ±32° window, at 50 nanotubes µm⁻¹, on 10 × 10 cm²substrates. Transistors (channel length of 1–5 µm) are fabricated parallel and perpendicular to the alignment. The parallel transistors perform with 7× faster charge carrier mobility (101 and 49 cm²V⁻¹s⁻¹assuming array and parallel‐plate capacitances, respectively) with high on/off ratio of 10⁵. The spatial uniformity varies ±10% in density, ±2° in alignment, and ±7% in mobility. Deposition occurs within seconds per wafer, and further substrate scaling is viable. Compared to random networks, aligned nanotube films promise to be a superior platform for applications including sensors, flexible/stretchable electronics, and light emitting and harvesting devices.