gebhart/patrepeval huggingface dataset:
Multiecho water‐fat separation and simultaneous <i>R</i> estimation with multifrequency fat spectrum modeling (2008)

Multiecho chemical shift-based water-fat separation methods are seeing increasing clinical use due to their ability to estimate and correct for field inhomogeneities. Previous chemical shift-based water-fat separation methods used a relatively simple signal model that assumes both water and fat have a single resonant frequency. However, it is well known that fat has several spectral peaks. This inaccuracy in the signal model results in two undesired effects. First, water and fat are incompletely separated. Second, methods designed to estimate T(2) (*) in the presence of fat incorrectly estimate the T(2) (*) decay in tissues containing fat. In this work, a more accurate multifrequency model of fat is included in the iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) water-fat separation and simultaneous T(2) (*) estimation techniques. The fat spectrum can be assumed to be constant in all subjects and measured a priori using MR spectroscopy. Alternatively, the fat spectrum can be estimated directly from the data using novel spectrum self-calibration algorithms. The improvement in water-fat separation and T(2) (*) estimation is demonstrated in a variety of in vivo applications, including knee, ankle, spine, breast, and abdominal scans.
Analysis and Synthesis of RFID Equivalent Circuits through Backscatter and ARS (2007)

RFID tags are assumed to function when being read and not to function when the reader does not see the tag. In actuality, the antenna/front end combination is an analog circuit that represents the result of both design and manufacturing. This circuit is a determinant in the minimum power to operate the manufactured tag. Other wireless devices such as passive sensor platforms require similar designs. This paper presents a method of analysis and considerations for design of passive devices that share similar front end structures with a focus on passive RFID tags.
Comparison of different electrical HVDC-architectures for aircraft application (2012)

This paper deals with an integration of High Voltage DC (HVDC <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> ) in the onboard power supply system. Conventional aircraft grids have a main voltage of 115 V AC (star voltage) with a variable frequency of 360...800 Hz. Newer aircraft try to integrate 230 V AC generators in the grid to save cable weight. With the “More Electric Aircraft”- concept HVDC grids could be integrated in future airplanes. In all concepts the airport infrastructure has to be considered. The ground power supply is based on mobile Ground Power Units (GPUs) or an inverter supplied by the airport grid (Fig. 1). The ground supply allocates 115 V AC with a fixed frequency of 400 Hz and a maximum power of 90 kVA per unit. Changing to an HVDC-grid has a lot of advantages. Higher voltage means lower cable weight. Furthermore, the electrical converter architecture can be optimized. Especially the converters inside the loads can be built much lighter when using a DC supply. This paper compares different possibilities of HVDC integration. Ancillary conditions like carbon fiber reinforced plastic fuselages and a possible ground power supply with conventional technology are taken into consideration. The attention is focused on an efficient cabin power supply. But to make a global assessment, the entire onboard power supply system is analyzed.
Shedding of the Urinary Biomarker Kidney Injury Molecule-1 (KIM-1) Is Regulated by MAP Kinases and Juxtamembrane Region (2007)

Kidney injury molecule-1 (KIM-1) is markedly upregulated in renal proximal tubule cells by stimuli that promote dedifferentiation, including ischemic or toxic injury, as well as in cases of tubulointerstitial disease, polycystic kidney disease, and renal cell carcinoma. Structurally, KIM-1 possesses a single transmembrane domain and undergoes membrane-proximal cleavage, which leads to the release of soluble KIM-1 ectodomain into the urine. Urinary KIM-1 ectodomain is a promising sensitive and specific biomarker for acute kidney injury in humans, and therefore it is important to determine what regulates KIM-1 shedding. We found that constitutive cleavage of KIM-1 is mediated by ERK activation, and that cleavage is accelerated by p38 MAP kinase activation. After cleavage, a 14-kD membrane-bound fragment of KIM-1, which contains two highly conserved tyrosine residues, was tyrosine-phosphorylated. Mutagenesis studies demonstrated that the juxtamembrane secondary structure, not the primary amino acid sequence, was critical to the cleavage of KIM-1.
Effects of a D-Cys6/L-Cys6 Interchange in Nonselective and Selective Vasopressin and Oxytocin Antagonists (1995)

We report the solid-phase synthesis of the D-Cys6 analogues of arginine-vasopressin (AVP), peptide 1, of the selective AVP vasopressor (V1a receptor) antagonist [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O-methyltyrosine]arginine-vasopressin (d(CH2)5[Tyr(Me)2]-AVP, (A)), peptide 2, of the three nonselective antidiuretic/vasopressor (V2/V1a receptor) AVP antagonists d(CH2)5[Tyr(Et)2]VAVP (B), d(CH2)5[D-Tyr(Et)2]VAVP (C), and d(CH2)5[D-Phe2]VAVP (D) (where V = Val4), peptides 3-5, of the nonselective oxytocin (OT) antagonists d(CH2)5-[Tyr(Me)2]OVT (E) and d(CH2)5[Tyr(Me)2,Thr4,Tyr-NH2(9)]OVT (F) (where OVT = ornithine-vasotocin), peptides 6 and 7, and of the selective OT antagonists desGly-NH2,d(CH2)5[Tyr(Me)2,Thr4]OVT (G) and d(CH2)5]D-Trp2,Thr4]OVT (H), peptides 8 and 9. We also present the repeat syntheses of the previously reported d(CH2)5[D-Trp2]AVT (peptide 10) and its D-Cys6 analogue (peptide 11) (where AVT = arginine-vasotocin). Peptides 1-11 were assayed for agonistic and antagonistic activities in in vivo V1a, V2, and oxytocic assays and in in vitro oxytocic assays without and with 0.5 mM Mg2+. With V2 and V1a agonistic potencies of 0.82 and 0.41 units/mg, [D-Cys6]AVP has retained less than 0.3% of the V2 and V1a potencies of AVP. It exhibits no oxytocic activity and is an in vitro OT antagonist. pA2 = 6.67 (no Mg2+); pA2 = 5.24 (0.5 mM Mg2+). By contrast, with one or two exceptions, a D-Cys6/L-Cys6 interchange in antagonists 2-9, although resulting in reductions of antagonistic potencies in all assays for virtually all peptides 2-9 relative to A-H, has been well tolerated. For peptides 2-5, the anti-V2 and anti-V1a pA2 values range from approximately 5.54 to 7.33 and from 7.19 to 8.06, respectively; the range of in vitro anti-OT pA2 values (no Mg2+) is 7.35-7.87; with 0.5 mM Mg2+, the range is 7.24-8.21. Peptides 2 and 4 have in vivo anti-OT pA2s = 6.60 and 7.16, respectively. For peptides 6-9, the range of in vitro anti-OT pA2 values (no Mg2+) is 7.65-7.96; with 0.5 mM Mg2+, the range is 7.41-7.65, and the in vivo anti-OT pA2 values range from 6.85 to 7.33. With an in vivo anti-OT pA2 = 7.33, peptide 6 is equipotent with its parent E. The in vivo anti-OT potencies of peptides 7-9 are significantly reduced relative to those of F-H. The in vitro anti-OT (0.5 mM Mg2+) pA2 values of 10 and 11 are 7.54 and 7.50, both significantly lower than those previously reported.(ABSTRACT TRUNCATED AT 400 WORDS)
"Troika Acids": Synthesis, Structure, and Fragmentation Pathways of Novel .alpha.-(Hydroxyimino)phosphonoacetic Acids (1995)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXT"Troika Acids": Synthesis, Structure, and Fragmentation Pathways of Novel .alpha.-(Hydroxyimino)phosphonoacetic AcidsBoris A. Kashemirov, Jing-Yue Ju, Robert Bau, and Charles E. McKennaCite this: J. Am. Chem. Soc. 1995, 117, 27, 7285–7286Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://pubs.acs.org/doi/10.1021/ja00132a045https://doi.org/10.1021/ja00132a045research-articleACS PublicationsRequest reuse permissionsArticle Views143Altmetric-Citations13LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts
Symmetries and multiferroic properties of novel room-temperature magnetoelectrics: Lead iron tantalate – lead zirconate titanate (PFT/PZT) (2011)

Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature multiferroic with magnetoelectric coupling: (PbZr0.53Ti0.47O3) (1-x)- (PbFe0.5Ta0.5O3)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 μC/cm2, which actually increases (to 40 μC/cm2) in the high-T tetragonal phase, representing an exciting new room temperature oxide multiferroic to compete with BiFeO3. Additional transitions at high temperatures (cubic at T&gt;1300 K) and low temperatures (rhombohedral or monoclinic at T&lt;250 K) are found. These are the lowest-loss room-temperature multiferroics known, which is a great advantage for magnetoelectric devices.
Selectivity of optical stimulation in the auditory system (2006)

It is known that electrical current injected from cochlear implant contacts spreads within the cochlea, causing overlapping stimulation fields and possibly limiting the performance of cochlear implant users. We have investigated an alternative mechanism to stimulate auditory neurons in the gerbil cochlea using a laser, rather than electrical current. With the laser, it is possible to direct the light to a selected, known volume of tissue that is smaller than the electrically stimulated population of cells. In the present experiments, a transiently expressed transcription factor, c-FOS, was used to stain activated nerve cells. Immunohistochemical staining for c-FOS in the cochlea shows a small area of optical stimulation, which occurs directly opposite to the optical fiber. Additionally, masking data indicate that the laser can stimulate a small population of cells similar to an acoustic toneburst. Smaller populations of stimulated cells could reduce the amount of overlap in stimulation fields and allow more stimulation contacts in a neuroprothesis.
Adaptive Document Layout via Manifold Content (2003)

We present and explore a simple idea for improving doc-ument layout on arbitrary devices of different resolutions and size. The key idea is to allow manifold representations of content: multiple versions of anything that might appear in a document, such as text, images, or even stylistic con-ventions. Content is then selected and formatted dynami-cally, on the fly, by a layout engine in order to best adapt to a given viewing situation. We propose a user interface for authoring and editing such manifold content, and sketch a few interesting new algorithms that make use of it. 1.
Gelcasting : a new ceramic forming process (1991)

Dans ce procede, une suspension de poudre ceramique dans une solution de monomeres organiques est coulee dans un moule. On polymerise in situ le melange de monomeres pour former des pieces gelifiees qui seront ensuite sechees et frittees. Le procede peut se pratiquer avec des dispersions aqueuses ou non-aqueuses. On presente les etudes realisees avec des systemes d'acrylamide.
Mining requirements from closed-loop control models (2013)

A significant challenge to the formal validation of software-based industrial control systems is that system requirements are often imprecise, non-modular, evolving, or even simply unknown. We propose a framework for mining requirements from the closed-loop model of an industrial-scale control system, such as one specified in the Simulink modeling language. The input to our algorithm is a requirement template expressed in Parametric Signal Temporal Logic --- a formalism to express temporal formulas in which concrete signal or time values are replaced by parameters. Our algorithm is an instance of counterexample-guided inductive synthesis: an intermediate candidate requirement is synthesized from simulation traces of the system, which is refined using counterexamples to the candidate obtained with the help of a falsification tool. The algorithm terminates when no counterexample is found. Mining has many usage scenarios: mined requirements can be used to validate future modifications of the model, they can be used to enhance understanding of legacy models, and can also guide the process of bug-finding through simulations. We present two case studies for requirement mining: a simple automobile transmission controller and an industrial airpath control model for an engine.
Highly doped phosphate glass fibers for fiber lasers and amplifiers with applications (2010)

Rare-earth doped fiber lasers and fiber amplifiers are highly attractive due to their efficiency, compactness, and, particularly, for their potential to various applications including communication systems, biomedical equipment, materials processing, LIDAR, and fiber-optic sensing. At the heart of these devices is the active fiber - most commonly based on silica host glass. However, the ability to dope silica glass fibers with high concentrations of erbium is limited due to clustering and nonlinear up-conversion - both of which degrade the efficiency of the gain fiber. Over many years, we have focused on developing highly doped phosphate glass fibers. The erbium concentrations can reach 4-5% weight erbium concentration without any negative effect to the optical gain. As a result, highly erbium doped phosphate glass fibers can produce large gain per unit length (typically 5 dB/cm) [1, 2]. This characteristic is a key enabler for a variety of optical devices that can make use of high optical gain in a short length - most notably high power single frequency fiber lasers and short length fiber amplifiers. In this presentation, we focus on two applications of the highly doped phosphate fiber. One is a high power, narrow linewidth single frequency fiber laser. The second is a fiber amplifier for coherent LIDAR applications capable of power scaling transform limited pulses without deleterious nonlinear effects. Both are examples of how this type of active fiber can lead to unique and superior performance.
ChemInform Abstract: CO<sub>2</sub> and Ambient Air in Metal—Oxygen Batteries: Steps Towards Reality (2015)

Abstract Review: 51 refs.
Micro-Optics in Single Crystal Diamond (2021)

Single crystal diamond has been widely recognized as an outstanding material for optics, yet precision shaping and structuring has traditionally proven challenging due to hardness and chemical inertness. We here summarize our recent advances in micro- and nanostructuring techniques demonstrating high quality micro-optical components in single crystal diamond.
Towards scalable production of a collagen-like protein from Streptococcus pyogenes for biomedical applications (2012)

These data have shown that recombinant bacterial collagen from S. pyogenes, can be produced in sufficient yield by a scalable microbial production process to give commercially acceptable yields for broad use in biomedical applications.
Studies on secretin. I. Synthesis of completely protected secretin. (1985)

In order to establish a new process for large-scale production of highly purified secretin, a synthesis based on a new strategy was investigated. A maximal protection method applying the HF deprotecting procedure in the final stage was employed. Six small protected fragments (2-6, 7-10, 11-13, 14-17, 18-22, 23-27) were each prepared by stepwise chain elongation. Thereafter, three protected fragments (1-10, 11-17, 18-27) were synthesized from them, and assembled to prepare the protected secretin. The optical purity of the product after each fragment condensation was checked by high performance liquid chromatography. Completely protected secretin having a high degree of chemical and optical homogeneity was obtained.
Unambiguous discrimination of two nonorthogonal multipartite states using local measurements and classical communication (Invited Paper) (2005)

We consider a quantum system of two nonorthogonal bipartite quantum states. We distribute the qubits between two parties, Alice and Bob. They each measure their qubits and then compare their measurement results to determine which state they were sent. This procedure is error-free, which implies that it must sometimes fail. In addition, no quantum memory is required; it is not necessary for one of the qubits to be stored until the result of the measurement on the other is known. We consider the cases in which, should a failure occur, both parties receive a failure signal or only one does. In the latter case, if the two states share the same Schmidt basis, the states can be discriminated with the same failure probability as would be obtained if the qubits were measured together. This scheme is sufficiently simple that it can be generalized to multipartite qubit and qudit states. Applications to quantum secret sharing are discussed.
The Nitric Oxide Cycle: Translational Regulation of Argininosuccinate Synthase by an Upstream Open Reading Frame (2006)

Argininosuccinate synthase (AS) catalyzes the rate‐limiting step in the recycling of citrulline to arginine, which in endothelial cells, is tightly coupled to the production of nitric oxide. Previous work has established that endothelial AS mRNA can be initiated from multiple start sites, generating mRNAs with different length, overlapping 5′‐UTRs. Nearly 10% of AS transcripts are longer variants that contain an out‐of‐frame, upstream open reading frame (uORF). Overexpression of this uORF suppresses AS expression while selective knockdown of the longer transcripts results in increased AS protein expression. To investigate the role of the AS uORF in the regulation of AS translation polysome profile analyses were performed. Real time RT‐PCR quantitation of RNA isolated from sucrose gradient fractions showed a substantial reduction of AS mRNA associated with ribosomes across the gradient when the AS uORF was overexpressed in endothelial cells as compared to the overexpression of a frame shifted mutant protein identical in size. The largest decrease in AS mRNA was observed in the polysome region. GAPDH mRNA distribution and levels were very similar under both conditions. To further support the role of the AS uORF in the regulation of AS translation, in vitro translation of AS mRNA in the presence of AS uORF protein showed a marked decrease in the translation of AS. Taken together, these results indicate that the AS uORF plays a significant role in the translational attenuation of AS expression in endothelial cells. (Supported by the AHA Grant 0455228B)
A Room Temperature Hydrogen Sensor With High Sensitivity and Selectivity Using Nanocrystalline Semiconductor Particles (2005)

Micro hydrogen sensor with interdigitated electrodes and indium doped nanopolycrystalline SnO2 particles was fabricated and tested. Giant sensitivity as high as 105 with good repeatability and recovery was observed. The sensor showed an excellant selectivity of hydrogen (H2) sensing over helium (He).
Elimination of heterojunction band discontinuities by modulation doping (1992)

Conduction- or valence-band discontinuities occurring at the junction of two heterogeneous semiconductors can be eliminated by appropriate doping of the interfacial region. We show by analytic and self-consistent calculations that simultaneous modulation doping and parabolic compositional grading result in flat band-edge potentials. The new concept is applied to distributed Bragg reflectors for vertical cavity lasers. The structures grown by molecular-beam epitaxy exhibit significantly lower resistances as compared to step-graded distributed Bragg reflectors.
COMPARISON OF SEVERAL METHODS FOR CALCULATING FRACTAL-BASED TOPOGRAPHIC CHARACTERIZATION PARAMETERS (1994)

The objective of this work is to compare fractal-based, topographic characterization parameters calculated by several different fractal analysis methods. Four fractal characterization methods (compass, patchwork, box counting, and 2-point correlation) are systematically applied to five topographic data sets, which encompass a wide range of scale, and the results are compared. The compass and patchwork methods calculate similar values for the fractal dimension and smooth/rough crossover. The box and 2-point correlation methods calculate similar values for the fractal dimension. The compass and patchwork methods are capable of calculating the smooth/rough crossover.
<title>Architecture for processing image algebra operations</title> (1992)

The proposed architecture is a logical design specifically for image algebra and other matrix related operations. The design is a fine grain SIMD concept consisting of three tightly coupled components: a spatial configuration processor, a weighting processor (point-wise), and an accumulation processor (point-wise). The flow of data and image processing operations are directed by a control buffer and pipe lined to each of the three processing components. The low-level abstraction of the proposed computational system is founded on the mathematical principle of discrete convolution and its geometrical decomposition. This geometrical decomposition combined with array processing requires redefining specific algebraic operations and reorganizing their order of parsing in the abstract syntax. The logical data flow of such an abstraction leads to a division of operations, those defined by point-wise operations, the others in terms of spatial configuration. The effect of this particular decomposition allows convolution type operations to be computed strictly as a function of the number of elements in the template (mask, filter, etc.) instead of the number of picture elements in the image. The potential utility of this architectural design lies in its ability to provide order statistic filtering and all the arithmetic and logic operations of the image algebra's generalized matrix product. The generalized matrix product is the most powerful fundamental formulation in the algebra, thus allowing a wide range of applications.
Bidirectional electrowetting actuation with voltage polarity dependence (2010)

This work presents an electrowetting system in which the actuation direction depends on the polarity of the applied voltage. Since electrowetting response depends on the voltage squared, it is typically independent of voltage sign to first order. However, the introduction of an electrochemical diode into the equivalent electrical circuit permits polarity-dependent behavior. Electrochemical diodes were created by making holes in the dielectric. The aluminum electrodes passivate and prevent current flow in one direction, creating diodelike electrical behavior with high breakdown voltage. The resulting actuation forces were directly measured and are of comparable magnitude for both actuation directions.