gebhart/patrepeval huggingface dataset:
Solar-Electric Dish Stirling System Development (1997)

Electrical power generated with the heat from the sun, called solar thermal power, is produced with three types of concentrating solar systems - trough or line-focus systems; power towers in which a centrally-located thermal receiver is illuminated with a large field of sun-tracking heliostats; and dish/engine systems. A special case of the third type of system, a dish/Stirling system, is the subject of this paper. A dish/Stirling system comprises a parabolic dish concentrator, a thermal receiver, and a Stirling engine/generator located at the focus of the dish. Several different dish/Stirling systems have been built and operated during the past 15 years. One system claims the world record for net conversion of solar energy to electric power of 29.4%; and two different company`s systems have accumulated thousands of hours of on-sun operation. Due to de-regulation and intense competition in global energy markets as well as the immaturity of the technology, dish/Stirling systems have not yet found their way into the marketplace. This situation is changing as solar technologies become more mature and manufacturers identify high-value niche markets for their products. In this paper, I review the history of dish/Stirling system development with an emphasis on technical and other issues that directly impact the Stirling engine. I also try to provide some insight to the opportunities and barriers confronting the application of dish/Stirling in power generation markets.
Structural Bone Allograft Combined with Genetically Engineered Mesenchymal Stem Cells as a Novel Platform for Bone Tissue Engineering (2007)

The presence of live periosteal progenitor cells on the surface of bone autografts confers better healing than devitalized allograft. We have previously demonstrated in a murine 4 mm segmental femoral bone-grafting model that live periosteum produces robust endochondral and intramembraneous bone formation that is essential for effective healing and neovascularization of structural bone grafts. To the end of engineering a live pseudo-periosteum that could induce a similar response onto devitalized bone allograft, we seeded a mesenchymal stem cell line stably transfected with human bone morphogenic protein-2/beta-galactosidase (C9) onto devitalized bone allografts or onto a membranous small intestinal submucosa scaffold that was wrapped around the allograft. Histology showed that C9-coated allografts displayed early cartilaginous tissue formation at day 7. By 6 and 9 weeks, a new cortical shell was found bridging the segmental defect that united the host bones. Biomechanical testing showed that C9-coated allografts displayed torsional strength and stiffness equivalent to intact femurs at 6 weeks and superior to live isografts at 9 weeks. Volumetric and histomorphometric micro-computed tomography analyses demonstrated a 2-fold increase in new bone formation around C9-coated allografts, which resulted in a substantial increase in polar moment of inertia (pMOI) due to the formation of new cortical shell around the allografts. Positive correlations between biomechanics and new bone volume and pMOI were found, suggesting that the biomechanical function of the grafted femur relates to both morphological parameters. C9-coated allograft also exhibited slower resorption of the graft cortex at 9 weeks than live isograft. Both new bone formation and the persistent allograft likely contributed to the improved biomechanics of C9-coated allograft. Taken together, we propose a novel strategy to combine structural bone allograft with genetically engineered mesenchymal stem cells as a novel platform for bone tissue engineering.
Improving robotic machining accuracy by real-time compensation (2009)

Although robotics based flexible automation is considered as an ideal solution for foundry pre-machining operation, very few successful installations have been seen due to many major challenges involved in robotic machining processes using conventional articulated robot, such as limited material removal rate, low surface quality, and chatter/vibration. This paper explains the reasons for low surface quality in robotic machining processes and analyzes the stiffness properties of robot structure. Then a real-time compensation algorithm based on a robot stiffness model and force control scheme is introduced. The experimental results show that much better surface quality can be achieved without extending the process cycle time.
U.S. Geographic Analysis of the Cost of Hydrogen from Electrolysis (2011)

This report summarizes U.S. geographic analysis of the cost of hydrogen from electrolysis. Wind-based water electrolysis represents a viable path to renewably-produced hydrogen production. It might be used for hydrogen-based transportation fuels, energy storage to augment electricity grid services, or as a supplement for other industrial hydrogen uses. This analysis focuses on the levelized production, costs of producing green hydrogen, rather than market prices which would require more extensive knowledge of an hourly or daily hydrogen market. However, the costs of hydrogen presented here do include a small profit from an internal rate of return on the system. The cost of renewable wind-based hydrogen production is very sensitive to the cost of the wind electricity. Using differently priced grid electricity to supplement the system had only a small effect on the cost of hydrogen; because wind electricity was always used either directly or indirectly to fully generate the hydrogen. Wind classes 3-6 across the U.S. were examined and the costs of hydrogen ranged from $3.74kg to $5.86/kg. These costs do not quite meet the 2015 DOE targets for central or distributed hydrogen production ($3.10/kg and $3.70/kg, respectively), so more work is needed on reducing the cost of wind electricity and the electrolyzers. If the PTC and ITC are claimed, however, many of the sites will meet both targets. For a subset of distributed refueling stations where there is also inexpensive, open space nearby this could be an alternative to central hydrogen production and distribution.
Deep Brain Stimulation Devices: A Brief Technical History and Review (2008)

Deep brain stimulation (DBS)--a broadly accepted therapeutic modality with tens of thousands of patients currently implanted--is the application of implantable electrical stimulation devices to treat neurological disorders. Approved indications include involuntary movement disorders; investigational applications include epilepsy, selected psychiatric disorders, and other conditions. DBS differs fundamentally from functional electrical stimulation and sensory prosthetics in that DBS therapies do not substitute for or replace injured tissues, organs, or body functions. DBS--targeted to particular brain nuclei or pathways that are specific for the disorder under treatment--influences brain function and behavioral output in ways that can relieve symptoms and improve the overall functioning of the patient. We will briefly review the history and present status of DBS from a technical and device-oriented perspective, with an eye toward future advances.
3D triangulation system based on out-of-axis aperture configuration for micro-scaled objects shape measurement (2011)

In three-dimensional (3-D) measurement systems based on triangulation, a stereoscopic angle between two distinct viewpoints encodes the depth information. This angle generally generates some distortion known as keystone distortion. In this paper an original 3-D optical configuration in addition with a digital light processing system (DLP) is presented which prevents keystone distortion, resulting in less calibration and post-processing work. The DLP is used to project incoherent white light fringes pattern at high frame rate (30 Hz) on a specimen and a CCD camera dynamically captures this projected pattern. Using a phase shifting algorithm, the reconstruction of the 3-D shape of the specimen is finally computed. This optical configuration is based on an « out of axis » aperture method combined with an afocal design for both projection and acquisition. With the combination of these two properties, the stereoscopic effect is obtained without any keystone distortion and a unique objective lens instead of two in a classical 3-D measurement system is used. As a result of this unique objective lens, the global volume of the measurement device can be easily minimized. This system was designed with the optical software Zemax to limit geometric and chromatic aberrations and to control the diffraction effect. Experiments showed that high surface profile accuracy can be obtained on a variety of surfaces, allowing reverse engineering on micro-scaled objects or precise 3-D measurements of macro-scaled objects. Also a depth resolution value under 2 μm for a scanned area around 7.5x5.5mm is obtained under experimental conditions.
Inhibition of Cyclooxygenase-2 Disrupts Tumor Vascular Mural Cell Recruitment and Survival Signaling (2006)

Much evidence supports an important role for the inducible enzyme cyclooxygenase-2 (COX-2) in tumor angiogenesis. Previous studies have focused on the role of COX-2 in stimulating endothelial proliferation, with blockade of this enzyme impairing endothelial homeostasis. However, recent data suggest that COX-2 also regulates molecules implicated in endothelial trafficking with pericytes/vascular mural cells (VMC), an interaction crucial to vessel stability. We investigated the role of COX-2 in vascular assembly by testing the effect of the specific COX-2 inhibitor SC-236 in an orthotopic xenograft model of human Wilms' tumor. Tumor growth was significantly suppressed by SC-236 (78% at day 28, 55% at day 35). Perfusion studies and immunostaining showed a marked decrease in vasculature, particularly in small vessels. Specifically, SC-236 inhibited participation of VMC in xenograft vessels. SC-236-treated tumors developed segmentally dilated, architecturally erratic tumor vessels with decreased nascent pericytes and scant mature VMC. Although vascular endothelial growth factor expression was unchanged, expression of the chemokine receptor CXCR4 was decreased in tumor vessels, consistent with defective homing of vascular progenitor cells. Vascular expression of phosphorylated platelet-derived growth factor receptor-beta was also diminished, indicating impaired VMC-endothelial trafficking. Consistent with the key role of this interaction in vessel homeostasis, vascular cells in SC-236-treated tumors displayed markedly diminished phosphorylated Akt, indicating disrupted survival signaling. These results show that SC-236 causes defective vascular assembly by attenuating incorporation of VMC into tumor vessels, impairing endothelial survival, and raise the possibility that blockade of COX-2 may provide therapeutic synergies with antiangiogenic molecules that more selectively target endothelial cells.
Revisiting twin-core fiber sensors for high-temperature measurements (2012)

A twin-core fiber Michelson interferometer is evaluated as a high-temperature sensor. Although linear and reproducible operation up to 300°C is obtained, at higher temperatures (700°C) the refractive index shifts plastically and hysteresis is observed, rendering an untreated sensor head unusable. The shift is shown to be greatly reduced by an annealing process of the fiber for 10 h at 900°C, with which the linear response is preserved.
Enzymatic Synthesis of Diacylglycerols Enriched with Conjugated Linoleic Acid by a Novel Lipase from <i>Malassezia globosa</i> (2012)

Abstract Diacylglycerols (DAG) of conjugated linoleic acid (CLA) were prepared by esterification of glycerol with fatty acids enriched with CLA (FFA–CLA, >95%) in the presence of a novel lipase from Malassezia globosa (SMG1). Lipase SMG1 is strictly specific to mono‐ and diacylglycerols but not triacylglycerols, which is similar to the properties of lipase from Penicillium camembertii (lipase G 50), but lipase SMG1 showed preference on the production of DAG with the reaction proceeding. Low temperature was beneficial for the conversion of FFA–CLA into acylglycerols, the degree of esterification reached 93.0% when the temperature was 5 °C. The maximum DAG content (53.4%) was achieved at 25 °C. The rate of DAG synthesis increased as the enzyme loading increased. However, at lipase amounts above 240 U/g mixtures, no significant increases in DAG concentration were observed. The molar ratio of FFA–CLA to glycerol and initial water content were optimized to be 1:3 (mol/mol) and 3%. Lipase SMG1 showed no regioselectivity because the contents of 1,3‐DAG and 1,2‐DAG were 43.1% and 21.2% based on total content of acylglycerols. By calculating the ratio of 9 c , 11 t ‐CLA to 10 t , 12 c ‐CLA, it was indicated that lipase SMG1 showed a little preference to 10 t , 12 c ‐CLA at the sn ‐1(3) position of monoacylglycerols (MAG), while no selectivity for 9 c , 11 t ‐CLA at the sn ‐2 position of DAG was obviously found.
All-optical extravascular laser-ultrasound and photoacoustic imaging of calcified atherosclerotic plaque in excised carotid artery (2018)

Photoacoustic (PA) imaging may be advantageous as a safe, non-invasive imaging modality to image the carotid artery. However, calcification that accompanies atherosclerotic plaque is difficult to detect with PA due to the non-distinct optical absorption spectrum of hydroxyapatite. We propose reflection-mode all-optical laser-ultrasound (LUS) imaging to obtain high-resolution, non-contact, non-ionizing images of the carotid artery wall and calcification. All-optical LUS allows for flexible acquisition geometry and user-dependent data acquisition for high repeatability. We apply all-optical techniques to image an excised human carotid artery. Internal layers of the artery wall, enlargement of the vessel, and calcification are observed with higher resolution and reduced artifacts with nonconfocal LUS compared to confocal LUS. Validation with histology and X-ray computed tomography (CT) demonstrates the potential for LUS as a method for non-invasive imaging in the carotid artery.
DNA of centuries-old timber can reveal its origin (2020)

Oak wood was highly appreciated and widely used for construction in past centuries. As population sizes expanded in some regions of Europe, local forests were depleted of high-quality timber. Therefore, regions of soaring economies were importing timber initially from the European market and eventually from other continents. Origin of archaeological or historical timber is usually identified by means of dendroprovenancing, i.e. statistical matching of tree-ring-width (TRW) series of timber of unknown origin with TRW reference datasets. However, this method has pitfalls and limitations and therefore alternative techniques are needed. Here, we used three different DNA analysis methods to investigate the potential of using ancient (a)DNA, extracted from oak timber derived from historical buildings and shipwrecks from a variety of countries. All the material had also been analysed dendrochronologically, so its dating and provenance is demonstrated. We included heartwood samples in this analysis, for which DNA extraction is especially challenging as it contains chemicals that inhibit DNA amplification. We succeeded in amplifying DNA for at least one marker from 56% of samples (including heartwood samples), yielding crucial information that allowed us to identify the potential source area of centuries old timber buildings in Latvia and Denmark and of 750-year-old shipwreck material from Germany. Our results prove the strong potential of DNA analyses for identifying timber origin to the regional scale, but by combining these with the dendrochronological results, we can control the exactitude of the aDNA approach and demonstrate a more nuanced examination of the timber sources for these historic structures.
Tied mixture continuous parameter modeling for speech recognition (1990)

The acoustic-modeling problem in automatic speech recognition is examined with the goal of unifying discrete and continuous parameter approaches. To model a sequence of information-bearing acoustic feature vectors which has been extracted from the speech waveform via some appropriate front-end signal processing, a speech recognizer basically faces two alternatives: (1) assign a multivariate probability distribution directly to the stream of vectors, or (2) use a time-synchronous labeling acoustic processor to perform vector quantization on this stream, and assign a multinomial probability distribution to the output of the vector quantizer. With a few exceptions, these two methods have traditionally been given separate treatment. A class of very general hidden Markov models which can accommodate feature vector sequences lying either in a discrete or in a continuous space is considered; the new class allows one to represent the prototypes in an assumption-limited, yet convenient way, as tied mixtures of simple multivariate densities. Speech recognition experiments, reported for two (5000- and 20000-word vocabulary) office correspondence tasks, demonstrate some of the benefits associated with this technique.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Efficacy of Sym004 in Patients With Metastatic Colorectal Cancer With Acquired Resistance to Anti-EGFR Therapy and Molecularly Selected by Circulating Tumor DNA Analyses (2018)

clinicaltrialsregister.eu Identifier: 2013-003829-29.
Comparison of Different Theoretical Models to Experimental Data on Viscosity of Binary Liquid Alloys (2007)

Six different theoretical equations are compared in the present paper with experimental data, measured for 28 binary liquid metallic systems. General conclusions are drawn on the ability of the different theoretical models to describe the concentration and temperature dependence of the viscosity of liquid alloys. A new equation is derived, being able to predict the viscosity in multicomponents alloy even if the viscosities of the pure components are not known.
Analytic transient solution of general MOS circuit primitives (1992)

The exact analytic transient solution is presented for a general MOS circuit primitive. In the circuit primitive, I-V characteristics of transistors are modeled by quadratic equations and node voltages by piecewise-linear waveforms. The proposed MOS circuit primitive, of which an inverter is a special case, is shown to be more suitable for switch level and fast timing simulations than the commonly used inverter. For circuit simulation of medium-size digital circuits containing a few hundred transistors, the application of this analytic solution has resulted in two to three orders of speed improvement over the conventional circuit simulator. The speed improvement factor is expected to grow with the circuit size. It is also shown that the exact transient solution of a macromodel which models the charge sharing can be obtained in the same way.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Simultaneous identification of campylobacters and prediction of quinolone resistance by comparative sequence analysis (1997)

Comparative sequence analysis of a 30-bp segment in the quinolone resistance-determining region of campylobacters not only allows for the detection of base changes associated with resistance but also is a powerful tool for species identification based on silent mutations.
Long-Term Effect of Retrobulbar Hematomas on the Vision of Cynomolgus Monkeys (1992)

Using the monkey model previously developed, we investigated the long-term effects of retrobulbar hematoma-induced retinal ischemia on functional vision and retinal histology. In this experimental model, ischemic periods of up to 120 minutes did not cause permanent visual deficits, as measured by flashed evoked visual potentials. Similarly, retinal histology showed no evidence of ischemic injury. From this we conclude that blindness after blepharoplasty is not due to retrobulbar hematomas alone and that additional predisposing factors are involved. The most likely additional factor is preexisting occult vascular ocular pathology.
Two‐dimensional vibrational correlation spectroscopy of in vitro hydroxyapatite maturation (2000)

Two-dimensional (2-D) Raman and 2-D IR correlation spectroscopy are applied to analyze changes in the ν4 region of the IR spectrum and in the ν1 region of the Raman spectrum during the maturation of hydroxyapatite (HA) following the solution-mediated conversion of amorphous calcium phosphate (ACP) to HA. The ν1 region of the Raman spectrum exhibits a frequency shift and sharpening during the maturation. Comparison of the experimental and simulated 2-D plots for this process suggests that the shift of a single peak, rather than a change in the relative intensity of two overlapped bands, is responsible for the observed spectral changes. The ν4 mode of the PO ion (T2 symmetry in the free species) splits into a triplet with components near 563, 575, and 603 cm−1 in HA. In addition, broad features appear at 540 and 617 cm−1. During the latest stages of the maturation, an OH− librational mode develops at ∼632 cm−1. Changes in the relative intensities of three components of the ν4 mode are not all correlated with each other. The synchronous 2-D plots reveal that the 563 and 603 cm−1 pair are positively correlated while the feature at 575 cm−1 is absent. A 587 cm−1 mode arising from ACP is negatively correlated with the 563 and 603 cm−1 pair and is both synchronously (positively) and asynchronously correlated with the 540 cm−1 feature during the early stages of the maturation but is absent from 2-D plots of the later stages of the maturation. Cross correlations between the ν4 mode and the ν1,ν3 contour generally confirm and extend previous assignments for the latter spectral region. Finally, the suitability of the 2-D approach for analysis of IR spectral images is examined through studies of HA crystallinity in a human iliac crest biopsy sample. Trabecular bone contains a fraction of HA that is more crystalline and mature than could be achieved in vitro during the room temperature ACP → HA interconversion. © 2000 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 57: 129–139, 2000
The structure of mullite, 2Al<sub>2</sub>O<sub>3</sub>.SiO<sub>2</sub>, and relationship with the structures of sillimanite and andalusite (1962)

A synthetic crystal of mullre, 2A120 a . SiO 2, was studied by X-ray diffraction methods. The structure was found to be describable as the result of the following changes imposed upon the structure of sillmanre: re-distribution of silicon and aluminium of tetrahedral coordination into a random way over the same set of positions, random removal of some of the oxygen atoms shared by the above cations, replacement of silicon by aluminium and shift of some of the cations of tetrahedral coordination into open sites. In terms of the structure thus described, decomposition of sillimanite and andalusite was interpreted as due to the formation of a stable arrangement of three aluminium atoms around an oxygen atom.