gebhart/patrepeval huggingface dataset:
Hallmarks of mechanochemistry: from nanoparticles to technology (2013)

The aim of this review article on recent developments of mechanochemistry (nowadays established as a part of chemistry) is to provide a comprehensive overview of advances achieved in the field of atomistic processes, phase transformations, simple and multicomponent nanosystems and peculiarities of mechanochemical reactions. Industrial aspects with successful penetration into fields like materials engineering, heterogeneous catalysis and extractive metallurgy are also reviewed. The hallmarks of mechanochemistry include influencing reactivity of solids by the presence of solid-state defects, interphases and relaxation phenomena, enabling processes to take place under non-equilibrium conditions, creating a well-crystallized core of nanoparticles with disordered near-surface shell regions and performing simple dry time-convenient one-step syntheses. Underlying these hallmarks are technological consequences like preparing new nanomaterials with the desired properties or producing these materials in a reproducible way with high yield and under simple and easy operating conditions. The last but not least hallmark is enabling work under environmentally friendly and essentially waste-free conditions (822 references).
Human Neural Progenitor Transplantation Rescues Behavior and Reduces α-Synuclein in a Transgenic Model of Dementia with Lewy Bodies (2017)

Synucleinopathies are a group of neurodegenerative disorders sharing the common feature of misfolding and accumulation of the presynaptic protein α-synuclein (α-syn) into insoluble aggregates. Within this diverse group, Dementia with Lewy Bodies (DLB) is characterized by the aberrant accumulation of α-syn in cortical, hippocampal, and brainstem neurons, resulting in multiple cellular stressors that particularly impair dopamine and glutamate neurotransmission and related motor and cognitive function. Recent studies show that murine neural stem cell (NSC) transplantation can improve cognitive or motor function in transgenic models of Alzheimer's and Huntington's disease, and DLB. However, examination of clinically relevant human NSCs in these models is hindered by the challenges of xenotransplantation and the confounding effects of immunosuppressant drugs on pathology and behavior. To address this challenge, we developed an immune-deficient transgenic model of DLB that lacks T-, B-, and NK-cells, yet exhibits progressive accumulation of human α-syn (h-α-syn)-laden inclusions and cognitive and motor impairments. We demonstrate that clinically relevant human neural progenitor cells (line CNS10-hNPCs) survive, migrate extensively and begin to differentiate preferentially into astrocytes following striatal transplantation into this DLB model. Critically, grafted CNS10-hNPCs rescue both cognitive and motor deficits after 1 and 3 months and, furthermore, restore striatal dopamine and glutamate systems. These behavioral and neurochemical benefits are likely achieved by reducing α-syn oligomers. Collectively, these results using a new model of DLB demonstrate that hNPC transplantation can impact a broad array of disease mechanisms and phenotypes and suggest a cellular therapeutic strategy that should be pursued. Stem Cells Translational Medicine 2017;6:1477-1490.
Strained GaInAsP/InP multiple‐quantum‐well lasers for wideband analog and high‐speed digital fiber‐optic networks (1994)

Abstract Compressively strained 1.3‐μm GaInAsP/InP multiple‐quantum‐well (MQW) lasers suitable for wide‐band analog and high‐speed digital transmissions were fabricated. With the ridge waveguide structure and an optimum well number, a large bandwidth of 11 GHz was achieved. The short‐cavity buried‐heterostructure lasers showed low threshold current (2 to 3 mA) and small turn‐on delay time (&lt;200 ps) at biasless 30‐mA pulse current. © 1994 John Wiley &amp; Sons, Inc.
Electrically based microstructural characterization : symposium held November 27-30, 1995, Boston, Massachusetts, U.S.A. (1996)

Impedance and/or dielectric spectroscopy are being used to monitor hydration in cements, flux solder in PC boards, sintering of ceramic materials, mechanical and environmental degradation of materials, etc. This is the first book from MRS to focus on the application of electrical measurements for the detection of microstructural features at all length scales (atomic to macroscopic). The electrical techniques discussed include dc and ac resistivity measurements, complex impedance analysis, multiplane analysis and various other methods such as electron energy loss spectroscopy, ellipsometry, capacitance voltage measurements and others. Research covers all classes of materials including electroceramics, biological materials, polymers, metals and a variety of composites. Advances in the techniques for the interpretation of data and monitoring of materials-related phenomena are emphasized. Topics include: advances in experimental techniques and applications; advances in interpretation of frequency dependence; characterization of defects; composition and structure profiling; electrode effects; grain boundary effects; composites and porous materials.
Circulating cell-free methylated DNA reveals tissue-specific, cellular damage from radiation treatment (2023)

Radiation therapy is an effective cancer treatment, although damage to healthy tissues is common. Here we analyzed cell-free, methylated DNA released from dying cells into the circulation to evaluate radiation-induced cellular damage in different tissues. To map the circulating DNA fragments to human and mouse tissues, we established sequencing-based, cell-type-specific reference DNA methylation atlases. We found that cell-type-specific DNA blocks were mostly hypomethylated and located within signature genes of cellular identity. Cell-free DNA fragments were captured from serum samples by hybridization to CpG-rich DNA panels and mapped to the DNA methylation atlases. In a mouse model, thoracic radiation-induced tissue damage was reflected by dose-dependent increases in lung endothelial and cardiomyocyte methylated DNA in serum. The analysis of serum samples from patients with breast cancer undergoing radiation treatment revealed distinct dose-dependent and tissue-specific epithelial and endothelial responses to radiation across multiple organs. Strikingly, patients treated for right-sided breast cancers also showed increased hepatocyte and liver endothelial DNA in the circulation, indicating the impact on liver tissues. Thus, changes in cell-free methylated DNA can uncover cell-type-specific effects of radiation and provide a readout of the biologically effective radiation dose received by healthy tissues.
Package Bidding for Spectrum Licenses (1997)

The FCC was an innovator in adopting the rules of the simultaneous ascending-price auction for its sales of spectrum licenses. While these rules have performed well in the auctions conducted so far (and would perform even better with the design improvements suggested in our first report), there are two inherent limitations in any design that seeks to assign and price the licenses individually. First, such designs create strategic incentives for bidders interested in multiple licenses that are substitutes to reduce their demands for some of the licenses in order to reduce the final prices of the others; this is the demand reduction problem. Second, even if bidders behave non-strategically, there is a fundamental problem with the basic concept of individual-license pricing when licenses are complementary. In simultaneous ascending-price auctions, from a bidder's perspective this is the exposure problem. A bidder who is unsuccessful in bidding for a large package of licenses may be left with a partial package whose total price cannot be justified in the absence of those complementary licenses it failed to win. This problem is present in any auction mechanism that sells licenses individually, with no opportunity to bid on packages. In this report our task is confined to analyses of the merits of package bidding and the practical problems of implementation. In our next report, we will outline proposals for the details of the procedural rules and other aspects of implementing a practical design, as well as the software development that would be necessary.
Ultralow Voltage Manipulation of Ferromagnetism (2020)

Spintronic elements based on spin transfer torque have emerged with potential for on-chip memory, but they suffer from large energy dissipation due to the large current densities required. In contrast, an electric-field-driven magneto-electric storage element can operate with capacitive displacement charge and potentially reach 1-10 µJ cm<sup>-2</sup> switching operation. Here, magneto-electric switching of a magnetoresistive element is shown, operating at or below 200 mV, with a pathway to get down to 100 mV. A combination of phase detuning is utilized via isovalent La substitution and thickness scaling in multiferroic BiFeO<sub>3</sub> to scale the switching energy density to ≈10 µJ cm<sup>-2</sup> . This work provides a template to achieve attojoule-class nonvolatile memories.
An experimental study of a flow-accelerating hydrokinetic device (2018)

Tidal energy researchers and developers use experimental testing of scaled devices as a method of evaluating device performance. Much of the focus to date has been on horizontal axis turbines. This study is focused on a novel vertical axis turbine which incorporates variable-pitch blades and a flow accelerator. The research involves laboratory testing of scale model devices in a recirculating flume. Computational fluid dynamic modelling is used to reproduce the measured flow data to investigate disparities in experimental data. The results show that the device is capable of achieving localised flow acceleration of up to a factor of 2 above the freestream velocity and achieved a mechanical power efficiency of 40%.
Phase Coupling and Control of Oxide-Based Oscillators for Neuromorphic Computing (2015)

Neuromorphic computing using neural network hardware has attracted significant interest as it promises improved performance at low power for data-intensive error-resilient graphical signal processing. Oscillatory neural networks (ONNs) use either frequency or phase as state variables to implement frequency-shift keying (FSK)- and phase-shift keying (PSK)-based neural networks, respectively. To make these ONNs power and area efficient, back-end-of-the-line compatible, and capable of processing multilevel information, we explore an emerging class of oscillators that show fine-grain frequency-tuning and phase-coupling. We examine TaOx- and TiOx-based oscillators (resistive random access memory-type) as elements of a neuromorphic compute block and experimentally demonstrate: 1) frequency control over four decades using a ballast MOSFET; 2) variable phase coupling between oscillators; and 3) variable phase programming between oscillators coupled with a MOSFET. Such fine-grain control over both frequency and relative phase serve as the desirable characteristics of oscillators required for multilevel information processing in star-type directly coupled FSK- and PSK-based neuromorphic systems that find applications in gray-scale image processing and other graphical compute paradigms. These attributes combined with the small size (<;1 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and simplicity, make these devices attractive candidates for realizing large-scale neuromorphic systems at reasonable size and power.
Frequency domain beamforming of ultrasound signals from inhomogeneous media using range Doppler method (2019)

Frequency domain beamforming methods, such as Stolt migration, yield efficient and fast processing of ultrasound data. Stolt migration, by migrating the individual element data in a 2-D frequency domain, improves processing speed by up to two orders of magnitude compared to conventional delay-and-sum (DAS) beamforming. However, as commonly implemented, it relies on the assumption that the speed-of-sound is constant, and is unable to be applied with advanced beamforming techniques such as phase aberration correction. Here, we demonstrate another approach to frequency domain beamforming, using the range-Doppler method developed for synthetic aperture radar imaging. The range-Doppler method is similar in speed to Stolt migration, but because it involves only a 1-D Fourier transform in array dimension, it can account for speed-of-sound inhomogeneities. We demonstrate our method with simulated channel signals of point targets and diffuse scatterers, and find similar image quality (e.g., mainlobe width, sidelobe levels, and contrast-to-noise ratio) to DAS beamforming in noise-free conditions. We further analyze signals acquired through a near-field phase-screen and from multi-layered media by modifying Doppler processing to correct for phase aberration and to account for the local sound-speed differences, respectively.
Colon Stem Cell and Crypt Dynamics Exposed by Cell Lineage Reconstruction (2011)

Stem cell dynamics in vivo are often being studied by lineage tracing methods. Our laboratory has previously developed a retrospective method for reconstructing cell lineage trees from somatic mutations accumulated in microsatellites. This method was applied here to explore different aspects of stem cell dynamics in the mouse colon without the use of stem cell markers. We first demonstrated the reliability of our method for the study of stem cells by confirming previously established facts, and then we addressed open questions. Our findings confirmed that colon crypts are monoclonal and that, throughout adulthood, the process of monoclonal conversion plays a major role in the maintenance of crypts. The absence of immortal strand mechanism in crypts stem cells was validated by the age-dependent accumulation of microsatellite mutations. In addition, we confirmed the positive correlation between physical and lineage proximity of crypts, by showing that the colon is separated into small domains that share a common ancestor. We gained new data demonstrating that colon epithelium is clustered separately from hematopoietic and other cell types, indicating that the colon is constituted of few progenitors and ruling out significant renewal of colonic epithelium from hematopoietic cells during adulthood. Overall, our study demonstrates the reliability of cell lineage reconstruction for the study of stem cell dynamics, and it further addresses open questions in colon stem cells. In addition, this method can be applied to study stem cell dynamics in other systems.
Ultra-low loss and compact coplanar waveguide crossing (2014)

We investigate the loss mechanism in 3-moded multimode-interference couplers that are the building blocks of a compact and low-loss waveguide crossing structure. Broadband silicon waveguide crossing arrays with <0.01dB insertion loss per crossing are proposed using cascaded multimode interference couplers, where lateral subwavelength nanostructures are used to reduce the insertions loss. We design and fabricate a 101×101 waveguide crossing array with a pitch of 3.08μm. Insertion loss of ~0.02dB per crossing and crosstalk <-40dB at 1550nm operating wavelength and broad transmission spectrum ranging from 1520 to 1610nm are experimentally demonstrated.
The representation space paradigm of concurrent evolving object descriptions (1992)

A representation paradigm for instantiating and refining multiple, concurrent descriptions of an object from a sequence of imagery is presented. It is designed for the perception system of an autonomous robot that needs to describe many types of objects, initially detects objects at a distance and gradually acquires higher resolution data, and continuously collects sensory input. Since the data change significantly over time, the paradigm supports the evolution of descriptions, progressing from crude 2-D 'blob' descriptions to complete semantic models. To control this accumulation of new descriptions, the authors introduce the idea of representation space, a lattice of representations that specifies the order in which they should be considered for describing an object. A system, TraX, that constructs and refines models of outdoor objects detected in sequences of range data is described.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
System for the design, manufacture, and testing of custom lenses with known amounts of high-order aberrations (2003)

Now that excimer laser systems can be programmed to correct complex aberrations of the eye on the basis of wave-front measurements, a method is needed to test the accuracy of the system from measurement through treatment. A closed-loop test method was developed to ensure that treatment plans generated by a wavefront measuring system were accurately transferred to and executed by the excimer laser. A surface was analytically defined, and a Shack-Hartmann-based wave-front system was used to formulate a treatment plan, which was downloaded to an excimer laser system. A plastic lens was ablated by the laser and then returned to the wave-front device, where it was measured and compared with the analytically defined wave-front surface. The two surfaces agreed up to 6th-order Zernike terms, validating the accuracy of the system.
Micron-gap spacers with ultrahigh thermal resistance and mechanical robustness for direct energy conversion (2019)

In thermionic energy converters, the absolute efficiency can be increased up to 40% if space-charge losses are eliminated by using a sub-10-µm gap between the electrodes. One practical way to achieve such small gaps over large device areas is to use a stiff and thermally insulating spacer between the two electrodes. We report on the design, fabrication and characterization of thin-film alumina-based spacers that provided robust 3-8 μm gaps between planar substrates and had effective thermal conductivities less than those of aerogels. The spacers were fabricated on silicon molds and, after release, could be manually transferred onto any substrate. In large-scale compression testing, they sustained compressive stresses of 0.4-4 MPa without fracture. Experimentally, the thermal conductance was 10-30 mWcm<sup>-2</sup>K<sup>-1</sup> and, surprisingly, independent of film thickness (100-800 nm) and spacer height. To explain this independence, we developed a model that includes the pressure-dependent conductance of locally distributed asperities and sparse contact points throughout the spacer structure, indicating that only 0.1-0.5% of the spacer-electrode interface was conducting heat. Our spacers show remarkable functionality over multiple length scales, providing insulating micrometer gaps over centimeter areas using nanoscale films. These innovations can be applied to other technologies requiring high thermal resistance in small spaces, such as thermophotovoltaic converters, insulation for spacecraft and cryogenic devices.
Phosphorylation site analysis of the anti-inflammatory and mRNA-destabilizing protein tristetraprolin (2007)

Tristetraprolin (TTP) is a member of the CCCH zinc finger proteins and is an anti-inflammatory protein. Mice deficient in TTP develop a profound inflammatory syndrome with erosive arthritis, autoimmunity and myeloid hyperplasia. TTP binds to mRNA AU-rich elements with high affinity for UUAUUUAUU nucleotides and causes destabilization of those mRNA molecules. TTP is phosphorylated extensively in vivo and is a substrate for multiple protein kinases in vitro. A number of approaches have been used to identify its phosphorylation sites. This article highlights the recent progress and different approaches utilized for the identification of phosphorylation sites in mammalian TTP. Important but limited results are obtained using traditional methods, including in vivo labeling, site-directed mutagenesis, phosphopeptide mapping and protein sequencing. Mass spectrometry (MS), including MALDI/MS, MALDI/MS/MS, liquid chromatography/MS/MS, immobilized metal ion affinity chromatography (IMAC)/MALDI/MS/MS and multidimensional protein identification technology has led the way in identifying TTP phosphorylation sites. The combination of these approaches has identified multiple phosphorylation sites in mammalian TTP, some of which are predicted by motif scanning to be phosphorylated by several protein kinases. This information should provide the molecular basis for future investigation of TTP's regulatory functions in controlling proinflammatory cytokines.
Selective etching process of SrBi2Ta2O9 and CeO2 for self-aligned ferroelectric gate structure (2004)

We have investigated an etch-stop process and fabricated the ferroelectric gate transistor without damage of source and drain regions using etching selectivity between etch rates of SrBi2Ta2O9 (SBT) and CeO2. The SBT and CeO2 were etched with inductively coupled plasma (ICP) reactive ion etching at various Ar/Cl2 gas mixing ratios, ICP powers, and rf bias powers. The etching selectivity of SBT/CeO2 was 6.8 and the vertical etching angle of SBT was 82° at the condition of 50% Cl2 concentration with the ICP power of 900 W and the rf bias power of 100 W. The characteristics of devices fabricated with an etch-stop process showed that there was no degradation of the ferroelectric characteristics and on/off ratio of programmable operation was 104.
Uplink Inter-Site Carrier Aggregation between Macro and Small Cells in Heterogeneous Networks (2014)

With uplink inter-site carrier aggregation (CA), it is possible to configure a user equipment (UE) to transmit on multiple layers (macro and small cells) simultaneously, each of which may exhibit different radio channel characteristics. This introduces new challenging issues such as how to configure the UEs with CA and how to assign UEs on different layers. In this paper, we propose an uplink inter-site CA configuration algorithm by taking some of the key factors into considerations (i.e., cell load conditions, UE transmission power constraint, and potential interference to other cells) when deciding whether UEs should be configured with uplink inter-site CA or not. Simulation results show that with proper configuration of UEs to operate with uplink inter-site CA, good user throughput gain compared to the case without inter-site CA can be achieved at low load due to larger bandwidth accessibility, but the CA gain decreases as the load increases.
Conformational Studies on Potential β‐Turn‐Forming Model Peptides (1985)

Abstract The conformational behavior of POE‐bound model peptides Boc‐( L ‐Ala) 2 ‐X‐Y‐( L ‐Ala) 2 ‐NHPOE (X – Y = L ‐Pro‐Gly ( I ), Gly‐ L ‐Ile ( II ); NHPOE = aminopoly(oxyethylene)) as well as of the repetitive hexapeptide of elastin, Boc‐ L ‐Val‐ L ‐Ala‐ L ‐Pro‐Gly‐ L ‐Val‐Gly‐A‐NHPOE‐M ( III ) (A = photosensitive 3‐nitro‐4‐(bromomethyl)benzoyl group; NHPOE‐M = aminopoly(oxyethylane) monomethyl ether) has been studied by means of 1 H‐NMR and CD spectroscopy. Compounds I and III form a β‐turn with Pro and Gly in positions i + 1 and i + 2, respectively, while an aggregated state for II , has been identified. The results are in good agreement with published prediction codes giving experimental evidence for the dominance of short‐range interactions to establish secondary structure in solution.