gebhart/patrepeval huggingface dataset:
Safe Online Gain Optimization for Cartesian Space Variable Impedance Control (2022)

Smooth behaviors are preferable for many contact-rich manipulation tasks. Impedance control provides an effective way to regulate robot movements by mimicking motions of a mass-spring-damping system. Consequently, the robot behavior can be determined by the impedance gains. However, tuning of the impedance gains for different tasks is not straightforward, especially for unstructured environments. Moreover, online adaption of the optimal gains to deal with the time-varying performance index is even more challenging. In this paper, we present Safe Online Gain Optimization for Cartesian space Variable Impedance Control (Safe OnGO-VIC) to overcome these challenges. By reformulating the dynamics of impedance control as a control-affine system, in which the impedance gains are the inputs, we provide a novel perspective to understand the relation between impedance gains and the robot behaviors. Furthermore, we innovatively formulate an optimization problem that utilizes force measurement collected online to obtain the optimal impedance gains in real-time. Safety constraints are also embedded in the proposed framework. We experimentally validated the proposed algorithm on three contact-rich manipulation tasks. Comparison results with a constant gain baseline and an adaptive control baseline prove that the proposed algorithm is effective and generalizable to different scenarios. Experiment videos are available at https://msc.berkeley.edu/research/safe-ongo-vic.html.
A Simulation Platform for Modeling Islanding Power Systems and its Application in Designing Stability Control Schemes (2010)

Because of the limitation of models in existing power system simulation softwares, only frequency fluctuations in a small range can be simulated in such environment. Relative bigger frequency fluctuations in islanding systems can not be simulated in them. To solve that problem, the OPC control logic of generating units was studied, and was simplified properly. The speed control model and protection model of generation units for islanding operation analysis were also developed in this paper. Furthermore, these models were set up in a user-defined environment of PSASP7.0 together, with other original components in the software, comprised a control simulation platform for islanding system operation. Its operational status was simulated and analyzed in a real system as an example, which proved that the reasonableness and practicality of the established simulation platform.
The influence of gaze stabilization and fixation on stepping reactions in younger and older adults. (2010)

The ability to maintain gaze fixation of an EF target may be important in reducing SL following a perturbation. Older adult subjects demonstrated a decreased ability to fixate a target during balance tasks while also displaying longer SLs.
Gain, detuning, and radiation patterns of nanoparticle optical antennas (2008)

For their capability to localize and redirect electromagnetic field, metal nanoparticles have been recently viewed as efficient nanoantenna operating in the optical regime. In this article, we experimentally investigated the optical responses of coupled gold antenna pairs and measured the critical parameters defining antenna characteristics: resonant frequencies and bandwidths, detuning and gains, and radiation patterns.
Kinetics of electron transfer reactions of H2-evolving cobalt diglyoxime catalysts. (2010)

Co-diglyoxime complexes catalyze H(2) evolution from protic solutions at modest overpotentials. Upon reduction to Co(I), a Co(III)-hydride is formed by reaction with a proton donor. Two pathways for H(2) production are analyzed: one is a heterolytic route involving protonation of the hydride to release H(2) and generate Co(III); the other is a homoytic pathway requiring association of two Co(III)-hydrides. Rate constants and reorganization parameters were estimated from analyses of laser flash-quench kinetics experiments (Co(III)-Co(II) self-exchange k = 9.5 x 10(-8) - 2.6 x 10(-5) M(-1) s(-1); lambda = 3.9 (+/-0.3) eV: Co(II)-Co(I) self-exchange k = 1.2 (+/-0.5) x 10(5) M(-1) s(-1); lambda = 1.4 (+/-0.05) eV). Examination of both the barriers and driving forces associated with the two pathways indicates that the homolytic reaction (Co(III)H + Co(III)H --> 2 Co(II) + H(2)) is favored over the route that goes through a Co(III) intermediate (Co(III)H + H(+) --> Co(III) + H(2)).
Efficient variable length channel coding for unknown DMCs (2004)

We present a strategy for the reliable communication of a message, in a variable number of channel uses, over an unknown discrete memoryless channel (DMC). The decoder periodically tests the received sequence and, when it can decode, sends an acknowledgment to the transmitter, which then stops transmitting. By choosing the size of the codebook large enough, the rate that is reliably realized by the strategy can be made to approach arbitrarily closely the mutual information between channel input and output induced by the user-chosen input distribution. The strategy presented can be considered as a generalization to arbitrary unknown DMCs of earlier variable length coding schemes, such as digital fountain codes for binary erasure channels (BECs), and a coding strategy for binary symmetric channels (BSCs) presented by Tchamkerten and Telatar
Diffusion, Thermal Properties and Chemical Compatibilities of Select MAX Phases with Materials For Advanced Nuclear Systems (2016)

The demands of Gen IV nuclear power plants for long service life under neutron irradiation at high temperature are severe. Advanced materials that would withstand high temperatures (up to 1000+ ºC) to high doses in a neutron field would be ideal for reactor internal structures and would add to the long service life and reliability of the reactors. The objective of this work is to investigate the chemical compatibility of select MAX with potential materials that are important for nuclear energy, as well as to measure the thermal transport properties as a function of neutron irradiation. The chemical counterparts chosen for this work are: pyrolytic carbon, SiC, U, Pd, FLiBe, Pb-Bi and Na, the latter 3 in the molten state. The thermal conductivities and heat capacities of non-irradiated MAX phases will be measured.
Pragmatism over principle (1999)

(1999). Pragmatism over principle. Bulletin of the Atomic Scientists: Vol. 55, Small Arms, Big Problem, pp. 16-17.
Flexible organic light-emitting diodes with transparent carbon nanotube electrodes: problems and solutions (2010)

We study in detail here the application of transparent, conductive carbon single-wall nanotube (SWNT) networks as electrodes in flexible organic light-emitting diodes (FOLEDs). Overall comparisons of these networks to the commonly used electrodes poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and indium tin oxide (ITO) are made, and SWNT networks are shown to have excellent optical and superior mechanical properties. The effects of protruding nanotubes, rough surface morphology, and SWNT network-adjacent layer dewetting are shown to be problematic, and approaches for addressing these issues are identified. The mechanical properties of SWNT networks and ITO are compared, and SWNT networks are shown to exhibit more durable sheet conductance under bending, which leads to bendable FOLEDs. We demonstrated FOLEDs with SWNT network anodes that exhibit outstanding light output and meet display requirements. SWNT-based FOLEDs show comparable lifetime performances to ITO-based devices. The promise and the remaining challenges for implementing SWNT networks in organic light-emitting diodes are discussed.
Inhibition of Staphylococcus aureus cysteine proteases by human serpin potentially limits staphylococcal virulence (2011)

Bacterial proteases are considered virulence factors and it is presumed that by abrogating their activity, host endogenous protease inhibitors play a role in host defense against invading pathogens. Here we present data showing that Staphylococcus aureus cysteine proteases (staphopains) are efficiently inhibited by Squamous Cell Carcinoma Antigen 1 (SCCA1), an epithelial-derived serpin. The high association rate constant (k(ass)) for inhibitory complex formation (1.9×10(4) m/s and 5.8×10(4) m/s for staphopain A and staphopain B interaction with SCCA1, respectively), strongly suggests that SCCA1 can regulate staphopain activity in vivo at epithelial surfaces infected/colonized by S. aureus. The mechanism of staphopain inhibition by SCCA1 is apparently the same for serpin interaction with target serine proteases whereby the formation of a covalent complex result in cleavage of the inhibitory reactive site peptide bond and associated release of the C-terminal serpin fragment. Interestingly, the SCCA1 reactive site closely resembles a motif in the reactive site loop of native S. aureus-derived inhibitors of the staphopains (staphostatins). Given that S. aureus is a major pathogen of epithelial surfaces, we suggest that SCCA1 functions to temper the virulence of this bacterium by inhibiting the staphopains.
Perspective review of what is needed for molecular-specific fluorescence-guided surgery (2018)

Molecular image-guided surgery has the potential for translating the tools of molecular pathology to real-time guidance in surgery. As a whole, there are incredibly positive indicators of growth, including the first United States Food and Drug Administration clearance of an enzyme-biosynthetic-activated probe for surgery guidance, and a growing number of companies producing agents and imaging systems. The strengths and opportunities must be continued but are hampered by important weaknesses and threats within the field. A key issue to solve is the inability of macroscopic imaging tools to resolve microscopic biological disease heterogeneity and the limitations in microscopic systems matching surgery workflow. A related issue is that parsing out true molecular-specific uptake from simple-enhanced permeability and retention is hard and requires extensive pathologic analysis or multiple in vivo tests, comparing fluorescence accumulation with standard histopathology and immunohistochemistry. A related concern in the field is the over-reliance on a finite number of chosen preclinical models, leading to early clinical translation when the probe might not be optimized for high intertumor variation or intratumor heterogeneity. The ultimate potential may require multiple probes, as are used in molecular pathology, and a combination with ultrahigh-resolution imaging and image recognition systems, which capture the data at a finer granularity than is possible by the surgeon. Alternatively, one might choose a more generalized approach by developing the tracer based on generic hallmarks of cancer to create a more "one-size-fits-all" concept, similar to metabolic aberrations as exploited in fluorodeoxyglucose - positron emission tomography (FDG-PET) (i.e., Warburg effect) or tumor acidity. Finally, methods to approach the problem of production cost minimization and regulatory approvals in a manner consistent with the potential revenue of the field will be important. In this area, some solid steps have been demonstrated in the use of fluorescent labeling commercial antibodies and separately in microdosing studies with small molecules.
Calcium Release-Activated Calcium (CRAC) Channel Inhibition Suppresses Pancreatic Ductal Adenocarcinoma Cell Proliferation and Patient-Derived Tumor Growth (2020)

Pancreatic ductal adenocarcinoma (PDAC) remains an unmet clinical problem in urgent need of newer molecularly driven treatment modalities. Calcium signals, particularly those associated with calcium release-activated calcium (CRAC) channels, are known to influence the development, growth, and metastasis of many cancers. This is the first study investigating the impact of CRAC channel inhibition on PDAC cell lines and patient-derived tumor models. PDAC cell lines were exposed to a novel CRAC channel inhibitor, RP4010, in the presence or absence of standard of care drugs such as gemcitabine and nab-paclitaxel. The in vivo efficacy of RP4010 was evaluated in a hyaluronan-positive PDAC patient-derived xenograft (PDx) in the presence or absence of chemotherapeutic agents. Treatment of PDAC cell lines with single-agent RP4010 decreased cell growth, while the combination with gemcitabine/nab-paclitaxel exhibited synergy at certain dose combinations. Molecular analysis showed that RP4010 modulated the levels of markers associated with CRAC channel signaling pathways. Further, the combination treatment was observed to accentuate the effect of RP4010 on molecular markers of CRAC signaling. Anti-tumor activity of RP4010 was enhanced in the presence of gemcitabine/nab-paclitaxel in a PDAC PDx model. Our study indicates that targeting CRAC channel could be a viable therapeutic option in PDAC that warrants further clinical evaluation.
Towards model-based development of decentralised peer-to-peer data vaults (2020)

Using centralised data storage systems has been the standard practice followed by online service providers when managing the personal data of their users. This method requires users to trust these providers and, to some extent, users are not in full control over their data. The development of applications around decentralised data vaults, i.e., encrypted storage systems located in user-managed devices, can give this control back to the users as sole owners of the data. However, the development of such applications is not effort-free, and it requires developers to have specialised knowledge, such as how to deploy secure and peer-to-peer communication systems. We present Vaultage, a model-based framework that can simplify the development of data vault applications. We demonstrate its core features through a social network application case study and include some initial evaluation results, showing Vaultage's code generation capabilities and some profiling analysis of the generated network components.
Strategies for quantum computing molecular energies using the unitary\n coupled cluster ansatz (2017)

The variational quantum eigensolver (VQE) algorithm combines the ability of\nquantum computers to efficiently compute expectation values with a classical\noptimization routine in order to approximate ground state energies of quantum\nsystems. In this paper, we study the application of VQE to the simulation of\nmolecular energies using the unitary coupled cluster (UCC) ansatz. We introduce\nnew strategies to reduce the circuit depth for the implementation of UCC and\nimprove the optimization of the wavefunction based on efficient classical\napproximations of the cluster amplitudes. Additionally, we propose an\nanalytical method to compute the energy gradient that reduces the sampling cost\nfor gradient estimation by several orders of magnitude compared to numerical\ngradients. We illustrate our methodology with numerical simulations for a\nsystem of four hydrogen atoms that exhibit strong correlation and show that the\ncircuit depth of VQE using a UCC ansatz can be reduced without introducing\nsignificant loss of accuracy in the final wavefunctions and energies.\n
An Introduction to Neural Information Retrieval t (2018)

Neural models have been employed in many Information Retrieval scenarios, including ad-hoc retrieval, recommender systems, multi-media search, and even conversational systems that generate answers in response to natural language questions. An Introduction to Neural Information Retrieval provides a tutorial introduction to neural methods for ranking documents in response to a query, an important IR task. The monograph provides a complete picture of neural information retrieval techniques that culminate in supervised neural learning to rank models including deep neural network architectures that are trained end-to-end for ranking tasks. In reaching this point, the authors cover all the important topics, including the learning to rank framework and an overview of deep neural networks. This monograph provides an accessible, yet comprehensive, overview of the state-of-the-art of Neural Information Retrieval.
Optical characterization of ZnO nanopillars on Si and macroporous periodic Si structure (2012)

ZnO nanopillars were successfully grown using both the vapor-liquid-solid and the aqueous chemical growth methods on different substrates, such as quartz, n-, and p-type non-porous Si wafer (flat) and microporous periodic Si structure (MPSiS). Scanning electron microscopy was employed to compare sample morphologies. The absorption was calculated employing the GW0 method, based on the local density approximation, and with the projector augmented wave approach. Experiment and theory show a reasonable agreement when the shape of the optical absorption is considered. The measured absorption of ZnO nanopillars, on different substrates, is lower than that observed for ZnO films on quartz substrate, in the energy gap spectral range. A strong effect of MPSiS substrates on ZnO nanopillar properties is observed. The photoluminescence technique was also employed as an optical characterization.
Certolizumab Pegol, Adalimumab and Infliximab Dramatically Reduce the Levels of TLR2, TLR4 and CD14 Expression on LPS-Stimulated Monocytes (2008)

Purpose: Purpose: Certolizumab pegol, adalimumab and infliximab have been shown to dramatically inhibit the LPS-stimulated production of inflammatory cytokines such as IL-1β by monocytes, whereas etanercept is considerably less potent at mediating this effect. 1 This function is thought to be initiated by signaling through membrane TNFα, although the exact mechanism is not completely understood. The aim of this study was to examine the effect of these anti-TNFα reagents on the levels of cell surface molecules such as Toll Like Receptor (TLR) 2 (CD282), TLR4 (CD284) and CD14, which are involved in the response to LPS. TLR2 and 4 levels have been shown to be upregulated during inflammation, particularly in Crohn's disease. Methods: Heparinised whole blood from healthy volunteers was incubated for 1 hour at 37°C with 10 μg/mL of 1 of the 4 anti-TNFα reagents to allow signaling through membrane TNF. Then 100 ng/mL LPS was added for 2 hours. The cells were stained with either phycoerythrin labeled anti-TLR2, -TLR4 or -CD14 antibody, and a fluorescein isothiocyanate labeled CD33 antibody. Erythrocytes were removed by hypotonic lysis and the samples were analysed by flow cytometry. The level of staining on monocytes was determined by gating the cells using the CD33 antibody staining and side scatter. Results: Certolizumab pegol, adalimumab and infliximab reduced the geometric mean level of TLR2 to 12.2, 18.1 and 14.6, respectively (LPS control was 50.6), TLR4 to 6.1 5.8 and 5.0, respectively (LPS control was 13.2), and CD14 to 47.0, 66.9 and 48.2, respectively (LPS control was 107). Etanercept reduced, to a lesser degree, the level of these 3 surface markers to 37.9, 11.1 and 60.6 for TLR2, TLR4 and CD14, respectively. Conclusion: Certolizumab pegol, adalimumab and infliximab, which have been shown to potently inhibit the LPS driven cytokine production by monocytes, all dramatically reduced the level of TLR2, 4 and CD14 on the cell surface of monocytes activated with LPS. This reduction in the levels of the surface markers could explain the unresponsiveness to LPS as there are less of these proteins on the cell surface to bind LPS and transfer the inflammatory signal into the cell. Etanercept did not reduce the levels of TLR2 and 4 to the same degree and does not potently inhibit the LPS-driven cytokine production. This mechanism of action could be important in Crohn's disease where bacteria are a major part of the inflammatory process.
Wide-Aperture MIMO via Reflection off a Smooth Surface (2023)

This paper provides a deterministic channel model for a scenario where wireless connectivity is established through a reflection off a smooth planar surface of an infinite extent. The developed model is rigorously built upon the physics of wave propagation and is as precise as tight are the unboundedness and smoothness assumptions on the surface. This model allows establishing how line-of-sight multiantenna communication is altered by a reflection off an electrically large surface, a situation of high interest for mmWave and terahertz frequencies.
Phase locking in a Nd:YVO_4 waveguide laser array using Talbot cavity (2013)

We demonstrated phase-locking in a laser-diode-array-pumped Nd:YVO₄ laser array (15 emitters) using a Talbot cavity. The Nd:YVO₄ slab crystal was coated by dielectric material for claddings and formed a planar waveguide for the vertical mode. To stabilize the horizontal array mode, periodical thermal lenses were generated by controlling the heat flow. The phase-locked waveguide array generated 1.65-W output power, while 2.02 W was available in a standard cavity. Two-peak supermode was demonstrated with the Talbot cavity and was converted to a single peak with a spatial light modulator. We also experimentally and numerically analyzed the characteristics of Talbot phase-locking.
Non‐Toxic Dry‐Coated Nanosilver for Plasmonic Biosensors (2010)

Abstract The plasmonic properties of noble metals facilitate their use for in vivo bio‐applications such as targeted drug delivery and cancer cell therapy. Nanosilver is best suited for such applications as it has the lowest plasmonic losses among all such materials in the UV‐visible spectrum. Its toxicity, however, can destroy surrounding healthy tissues and thus, hinders its safe use. Here, that toxicity against a model biological system ( Escherichia coli ) is “cured” or blocked by coating nanosilver hermetically with a about 2 nm thin SiO 2 layer in one‐step by a scalable flame aerosol method followed by swirl injection of a silica precursor vapor (hexamethyldisiloxane) without reducing the plasmonic performance of the enclosed or encapsulated silver nanoparticles (20–40 nm in diameter as determined by X‐ray diffraction and microscopy). This creates the opportunity to safely use powerful nanosilver for intracellular bio‐applications. The label‐free biosensing and surface bio‐functionalization of these ready‐to‐use, non‐toxic (benign) Ag nanoparticles is presented by measuring the adsorption of bovine serum albumin (BSA) in a model sensing experiment. Furthermore, the silica coating around nanosilver prevents its agglomeration or flocculation (as determined by thermal annealing, optical absorption spectroscopy and microscopy) and thus, enhances its biosensitivity, including bioimaging as determined by dark field illumination.