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The present disclosure is directed to systems and methods for synthesizing a spidroin. In some embodiments, the methods comprise synthesizing a monomer in vivo in a heterologous host, the monomer comprising an N-terminus IntC domain and a C-terminus IntN domain, and post-translationally polymerizing the synthesized monomer via in vitro split-intein mediated polymerization.
Methods and apparatus for managing circular queues are disclosed. A pointer designates an index position of a particular queue element and contains an additional pointer state, whereby two pointer values (split indexes) can designate the same index position. Front and rear pointers are respectively managed by dequeue and enqueue logic. The front pointer state and rear pointer state distinguish full and empty queue states when both pointers designate the same index position. Asynchronous dequeue and enqueue operations are supported, no lock is required, and no queue entry is wasted. Hardware and software embodiments for numerous applications are disclosed.
The enclosed disclosure relates to hybrid vehicles and systems with an engine, a drivetrain with a clutch and a transmission, an electric machine, and a controller. The controller receives lookahead information within a lookahead window and present state information of the hybrid vehicle. The controller determines a predicted coasting opportunity exceeding a predetermined threshold within the lookahead window and determines a cruise control reference speed, a power split between the engine and the electric machine, and a timing of enabling engine-off coasting during the coasting opportunity. The controller deactivates the engine and disengages the clutch at a start of the coasting opportunity when the engine-off coasting is enabled.
A method of electrocatalytic water splitting by providing an anode and a cathode; and utilizing the anode and the cathode for alkaline water electrolysis. Each of the anode and the cathode comprises a uniform distribution of a bifunctional electrocatalyst comprising metallic phosphides on a conductive substrate. The metallic phosphides comprise arion phosphide (FeP) and dinickel phosphide (Ni 2 P). The bifunctional electrocatalyst promotes hydrogen evolution reaction (HER) at the cathode, and oxygen evolution reaction (OER) at the anode.
The present disclosure relates to a system for detecting and analyzing droplets of feedstock material being ejected from an additive manufacturing device. The system makes use of a split ring resonator (SRR) probe including a ring element having a gap, with the gap being positioned adjacent a path of travel of the droplets of feedstock material. An excitation signal source is used for supplying an excitation signal to the SRR probe. An analyzer analyzes signals generated by the SRR probe in response to perturbations in an electric field generated by the SRR probe as the droplets of feedstock material pass the ring element. The signals are indicative of dimensions of the droplets of feedstock material.
Systems, methods, circuits, and devices for providing and using transistors in a physically unclonable function (PUF) circuit. The transistors comprise a split source drain configuration including one or more inflection segments that increase process variations between the transistors such that each transistor generates a unique output signal.
Multi-split variable refrigerant flow (VRF) systems are highly energy-efficient HVAC (heating, ventilation and air conditioning) technologies that connect a single outdoor unit to multiple independent indoor terminal units using a common refrigerant circuit and a variable-speed compressor. Building energy simulations that incorporate VRF systems help model their unique operational characteristics and predict energy consumption in specific building designs. Traditionally, EnergyPlus models these systems by employing multiple sets of performance curves to characterize both individual terminal units and the outdoor unit. However, producing these curves is labor intensive and error prone, and they often do not capture all the key input and output variables. This paper introduces a novel approach that uses multi-dimensional performance maps to model VRF systems in building environments for space cooling. In this approach, performance maps are developed at the component level—separately for the outdoor unit and for each indoor terminal. The new modeling method is validated within EnergyPlus via a Python plug-in that contains a simple solver loop to coordinate the component-level, indoor, and outdoor unit maps. Furthermore, because performance maps can span more variables than traditional performance curves, they offer the opportunity to implement advanced controls, such as enhanced dehumidification and compressor modulation. A VRF air conditioner’s hardware system was modeled using the DOE/ORNL Heat Pump Design Model, which was automated to produce extensive performance maps for both the indoor and outdoor units.
Nonprecious transition metal-organic frameworks (MOFs) are one of the most promising precursors for developing electrocatalysts with high porosity and structural rigidity. This study reports the synthesis of high efficiency electrocatalysts based on S-doped NiFeP. MOF-derived S-doped NiFeP structure is synthesized by a one-step phosphorization process with using S-doped MOFs as the precursor, which is more convenient and environment friendly, and also helps retain the samples’ framework. The oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance of the NiFeP catalysts can be improved after partially replacing P by S due to the tunable electronic structure. The optimized CCS-NiFeP-10 reaches a current density of 10 mA cm –2 for OER with an overpotential of 201 mV and outperforms most NiFe-based catalysts. The S doping plays an important role in tuning the ΔG values for intermediates formation in Ni atoms to a suitable value and exhibits a pronouncedly improved the OER performance. CCS-NiFeP-20 sample presents excellent HER performance due to the d-band center downshifting from the Fermi level. When the voltage of the electrolytic cell is 1.50 V, a current density of 10 mA cm –2 can be obtained. This strategy paves the way for designing highly active none-noble metal catalysts.
The main protease enzyme (Mpro) of coronaviruses cleaves the viral polyprotein into functional units essential for virus replication. Prior work has demonstrated that Mpro functions as a homodimer. However, studies on the mechanism of dimerization have been challenging because the purified protease is mostly dimeric, dimerization-defective mutants lack proteolytic activity, and robust cell-based assays have yet to be reported. To enable work on Mpro dimerization, we have developed a quantitative luciferase-based SARS-CoV-2 (SARS2) Mpro biosensor that accurately reports protein dimerization in living cells and, upon purification, also in vitro. Co-transfection of cells with a construct expressing Mpro fused to the 18 kDa LargeBiT of luciferase (LgBiT) and a second construct with Mpro fused to the 1 kDa SmallBiT of luciferase (SmBiT) results in a reconstitution of luciferase activity in a dose-dependent manner that requires conserved residues within the dimerization interface. Proteolytic activity is dispensable for dimerization and, uniquely, a C145A catalytically inactive mutant exhibits enhanced dimerization signal likely due to lower cytotoxicity. Mpro enzymes from multiple different coronaviruses also dimerize in this system, indicating mechanistic conservation. Interestingly, this dimerization biosensor also provides a quantitative read-out of inhibitor-facilitated dimerization. Covalent SARS2 Mpro inhibitors such as nirmatrelvir cause a 3- to 5-fold increase in luciferase activity. Together with corroborating structural, biophysical, and molecular dynamics experiments, our studies support a model in which covalent Mpro inhibitors such as nirmatrelvir simultaneously block catalytic activity and induce allosteric stabilization of the dimeric complex.
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Two-dimensional (2D)-structured photocatalysts with atomically thin layers not only have the potential to enhance hydrogen generation efficiency but also allow more direct investigations of the effects of surface terminations on photocatalytic activity. In this work, taking 2D Bi 2 WO 6 as a model, we found that the configuration of bilayer Bi 2 O 2 sandwiched by alternating WO 4 layers enabled the thermodynamic driving potential for photocatalytic hydrogen evolution. Without Pt deposition, the H 2 generation efficiency can reach to 56.9 μmol/g/h by 2D Bi 2 WO 6 as compared with no activity of Bi 2 WO 6 nanocrystals under simulated solar light. This configuration is easily functionalized by adsorption of Cl – /Br – to form Bi–Cl/Bi–Br bonds, which leads to the decrease of recombination in photogenerated charge carriers and narrower band gaps. This work highlights an effective way to design photocatalysts with efficient hydrogen evolution by tuning the surface terminations.
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Photocurrent density in excess of 10 mA cm −2 reported on 2.0 eV CuInGaS 2 solar cells integrated on SnO 2 :F substrates, yet new wide bandgap n-type buffers required to achieve higher photoconversion efficiency.
Generating hydrogen from local energy resources such as solar or wind would unlock a low-carbon energy carrier that could be used to reduce greenhouse gas emissions in sectors such as industry and transportation. Yet, the allocation of new or existing power generation solely to hydrogen production remains contentious due to disputes regarding emissions accounting. Photocatalytic (PC) hydrogen production technologies offer a unique solution, as hydrogen is produced directly from solar energy and water, without the need for electricity generation. However, cost projections for all photocatalytic designs to date have suggested that they are not cost competitive compared to conventional electrolysis systems manufactured at scale. Herein, we offer the first illustrative benchmark of cost and carbon intensity of hydrogen produced in a type 2 “Z-scheme” photocatalytic reactor design, which employs suspended semiconducting nanoconductor particles organized into two stacked volumes in a raceway design. The “Z-scheme” system utilizes two separate photoabsorber particles, tuned to drive either the hydrogen evolution reaction or the oxygen evolution reaction individually, connected via a reversible, charge transfer redox couple in solution. Furthermore, the results suggest a highly competitive and scalable technology, that justifies further experimental validation and prototyping in the field.