Publications

Polyketide synthase (PKS) enzymes have a modular, deterministic logic that holds the potential to act as a flexible chemical factory for the biological production of a huge diversity of valuable small molecule compounds. However, engineering a custom PKS to produce a specific desired product currently requires years of trial and error, for reasons that remain poorly understood. In this project, we have developed a rapid, high throughput, Design-Build-Test-Learn (DBTL) cycle for polyketide synthases (PKSs) and demonstrate its utility for production of materials precursors. The objectives are 1) to develop a rapid, high-throughput (HT) DBTL cycle for PKSs that will enable production of a large number of unnatural, organic molecules on demand at high titer, rate, and yield (TRY); 2) to demonstrate the utility of the PKS DBTL cycle to produce three molecules: one commodity chemical (caprolactam or valerolactam) and two novel materials precursors (caprolactam or valerolactam derivatives); and 3) to demonstrate the utility of the PKS DBTL cycle to increase the TRY of one molecule (caprolactam or valerolactam). In this project, we have successfully demonstrated our high throughput PKS DBTL pipeline, and have biologically produced valerolactam and several other novel nylon monomers.

abstract The Koyna earthquake (surface-wave magnitude 6.5) occurred on December 11, 1967 near Koyna Dam in a region of India which was considered to be stable and nearly nonseismic. The relationship between the recent increase in number of earthquake occurrences in the vicinity of Koyna Dam and the filling of the reservoir behind the dam is discussed. The response of the dam to the strong ground motion recorded during the Koyna earthquake is analyzed by the finite element method including dynamic effects of the reservoir. The cracking anticipated in the monoliths of Koyna Dam on the basis of stresses obtained from these analyses and strength of concrete in the dam is consistent with the earthquake damage. On the basis of analytical results, it would be useful to provide relatively higher strength concrete in selected parts of gravity dams; appropriate suggestions are made in this connection. Present design criteria need to be improved to recognize that significant tensile stresses occur in gravity dams during earthquakes and to provide for the consequences of these tensile stresses.

Model-based object recognition and object localization are fundamental tasks in industrial automation. In this article, we present a system that quickly recognizes (5 μs) and accurately localizes (0.025 mm) objects using a scanning beam sensor that consists of an array of binary light-beam sensors. Our scanning beam sensor is robust, inexpensive, compact, precise, and insensitive to ambient light, which are all prerequisites for industrial manufacturing applications. Scanning beam sensing involves moving objects with respect to the sensor and record ing the manipulator positions when the sensor outputs change. The recognition problem and the localization problem share the correspondence subproblem, the task of interpreting the sensed data in terms of model features. In this article, we present a constant-time indexing correspondence algorithm. Indexing in volves discretizing the sensed data to achieve integral indices, and using these indices to look up a table entry containing the correspondence information (the consistent model feature inter pretations). Complete indexing tables are crucial for scanning beam sensing, and for sparse sensing strategies in general, because each experiment only produces a handful of indexing coordinates. Constructing complete indexing tables has previ ously been an open problem (Clemens and Jacobs 1991). In this article, we describe a method for constructing complete indexing tables by enumerating the cells in an arrangement in configuration space.

Mutations at the act1, fadA, fadB, fadC, and fadD loci of Arabidopsis thaliana affect the fatty acid composition of the chloroplast membrane lipids. The mutations were mapped by measuring the fatty acid composition by gas chromatography of more than 3,300 leaf samples from individuals in segregating populations. Linkage analysis of the act1 mutant indicated that it is 35 cM from the an locus on chromosome 1. The fadA locus is on chromosome 4, where it is 18 cM from cer2 and tightly linked to ap2. The fadB locus is on chromosome 3, where it is 28 cM from gl1 and tightly linked to hy2. The fadC locus is 13 cM from ap2 and is tightly linked to cer2 on chromosome 4. The fadD locus is on chromosome 3, where it is 40 cM from gl1 and 3 cM from hy2.

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Summary form only given. Tunneling Field Effect Transistors (TFETs) have the potential to achieve a low operating voltage by overcoming the thermally limited subthreshold swing of 60mV/decade, but results to date have been unsatisfying. Unfortunately, TFETs have only shown steep subthreshold swings at low currents of a nA/μm or lower while we would like a mA/μm. To understand this we need to consider the two switching mechanisms in a TFET. The gate voltage can be used to modulate the tunneling barrier thickness and thus the tunneling probability as shown Fig. 1(a). Alternatively, it is possible use energy filtering or density of states (DOS) switching as illustrated in Fig. 1(b). If the conduction and valence band don't overlap, no current can flow. Once they do overlap, current can flow.

The successful utilization of ammonia in allylation reactions has little precedent (see: T. Nagano, S. Kobayashi J. Am. Chem. Soc. 2009, 131, 4200). The authors disclose a more general mono-allylation of ammonia through the development of an iridium-phosphoramidite complex which is stable to a large excess of the simple amine. The authors report a good variety of chiral amine products in high enantioselectivities and moderate yields.

Article Interfacing reality (panel): exploring emerging trends between humans and machines Share on Authors: Eric Paulos University of California, Berkeley University of California, BerkeleyView Profile , John Canny University of California, Berkeley University of California, BerkeleyView Profile , Eduardo Kac School of the Art Institute of Chicago School of the Art Institute of ChicagoView Profile , Ken Goldberg University of California, Berkeley University of California, BerkeleyView Profile , Mark Pauline Survival Research Laboratories Survival Research LaboratoriesView Profile , Stelarc Performance Artist Performance ArtistView Profile Authors Info & Claims SIGGRAPH '97: Proceedings of the 24th annual conference on Computer graphics and interactive techniquesAugust 1997 Pages 448–451https://doi.org/10.1145/258734.258904Online:03 August 1997Publication History 0citation384DownloadsMetricsTotal Citations0Total Downloads384Last 12 Months0Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access

Many inference services based on large language models (LLMs) pose a privacy concern, either revealing user prompts to the service or the proprietary weights to the user. Secure inference offers a solution to this problem through secure multi-party computation (MPC), however, it is still impractical for modern LLM workload due to the large overhead imposed by MPC. To address this overhead, we propose Marill, a framework that adapts LLM fine-tuning to minimize MPC usage during secure inference. Marill introduces high-level architectural changes during fine-tuning that significantly reduce the number of expensive operations needed within MPC during inference, by removing some and relocating others outside MPC without compromising security. As a result, Marill-generated models are more efficient across all secure inference protocols and our approach complements MPC-friendly approximations for such operations. Compared to standard fine-tuning, Marill results in 3.6-11.3x better runtime and 2.4-6.9x better communication during secure inference across various MPC settings, while typically preserving over 90% performance across downstream tasks.

Here, we report an efficient way to produce homogeneous Pt nanoparticles within a well-defined size range (3.5-6.6 nm) as a result of the seeded growth procedure using Pluronic L64 polymer capping agent. First, small seeds (3.5 nm) were prepared by the reduction of H2PtCl6.6H2O in water with NaBH4 in the presence of the capping poly(ethylene oxide)13-poly(propylene oxide)30-poly(ethylene oxide)13 triblock copolymer at room temperature. Additional anionic Pt salt was then introduced under flowing H2 to obtain larger nanoparticles.

In order to promote the effectiveness of hydrogen water chemistry (HWC) and to achieve a more effective reduction in electrochemical corrosion potential (ECP) in the primary coolant circuits of boiling water reactors (BWRs), the technology of noble metal chemical addition (NMCA) was brought into practice about 10 years ago. NMCA aims at enhancing the oxidation of hydrogen on metal surfaces and lowering the concentrations of the oxidants (oxygen and hydrogen peroxide) via recombination with hydrogen on the catalyzed surfaces, and therefore reducing the corrosion potentials of the structural alloys in a BWR primary heat transport circuit. Previous research indicates that the effectiveness of NMCA in combination with a low HWC might be evaluated via model predictions of the hydrogen-to-oxidant molar ratio (MH/O) in the primary coolant circuit. If the MH/O at a certain location is calculated to be greater than 2, it is justified that the NMCA would be effective in reducing the ECP to much below the critical potential for Intergranular Stress Corrosion Cracking (IGSCC), EIGSCC, of --0.23 VSHE. However, this statement is true only when the recombination efficiency of hydrogen with oxygen and/or hydrogen peroxide at the location of interest is 100%. Otherwise, significant amounts of oxidants may still be present, even with a stoichiometric MH/O of greater than 2. With the aid of a computer model DEMACE, we explored the impact of incomplete recombination and found that the ECP might be reduced under given circumstances, but not to a great extent, and might remain well above EIGSCC. Accordingly, considerable caution should be exercised upon using the MH/O as a sole indicator for evaluating the effectiveness of NMCA with low HWC as a means of mitigating IGSCC in a BWR. An important finding of this study is that it is necessary to quantify the recombination efficiencies of hydrogen with oxygen and/or hydrogen peroxide on the noble metal treated stainless steel surfaces in order to qualify the use of MH/O as an indicator for NMCA effectiveness in the primary coolant circuit of a BWR.