gebhart/patrepeval huggingface dataset:
Electrocaloric effect in the relaxor ferroelectric polymer composition P(VDF–TrFE–CFE)<sub>0.90</sub>–P(VDF–CTFE)<sub>0.10</sub> (2010)

The electrocaloric effect (ECE), i.e., the change of the temperature of the electrocaloric material due to the applied electrical field under adiabatic conditions, is a very attractive phenomenon used in a broad range of applications, for example in an electrical refrigerator. The first observations of a giant ECE were made by indirect measurements of the electrical polarization and not by direct measurements of the ECE itself. In our case, this effect was measured directly. Here a method and analysis of these direct measurements are presented and the obtained results are shown for P(VDF–TrFE–CFE) relaxor terpolymers blend with 10% composition of P(VDF–CTFE) copolymers.
A high resolution on-chip beat frequency detection system for measuring BTI, HCI, and TDDB (2010)

We present an on-chip reliability monitor capable of separating the aging effects of Hot Carrier Injection (HCI), Bias Temperature Instability (BTI), and Time Dependent Dielectric Breakdown (TDDB) with high frequency resolution. Sub-μs measurements are controlled by on-chip logic in order to avoid excessive unwanted BTI recovery during stress interruptions. Frequency shift measurement resolution of down to the error floor of 0.07% is achieved during these short interruptions using a beat frequency detection system, and we automate the experiments through a simple digital interface. Measurement results are presented from a 65 nm test chip.
Three‐dimensional gradients of voltage during development of the nervous system as invisible coordinates for the establishment of embryonic pattern (1995)

We are interested in the generation of endogenous electric fields associated with ionic currents driven through the vertebrate embryo by the transepithelial potential of its surface ectoderm. Using a non-invasive vibrating electrode for the measurement of ionic current, we have provided measurements of currents traversing amphibian embryos, and a preliminary report of the internal, extracellular voltage gradient under the neural plate which polarizes the embryo in the rostral/caudal axis (Metcalf et al. [1994] J. Exp. Zool. 268:307-322). Here we complete a description of this gradient in electrical potential (ca. 10 mV/mm, caudally negative), describe a simultaneous gradient organized in the medial/lateral axis (ca. 5-18 mV/mm, negative at the margins of the neural folds), and describe their appearance and disappearance during ontogeny of the axolotl embryo. Both voltage gradients are not expressed until neurulation, and disappear at its climax. This appearance and disappearance correlates with the shunting of current out of the lateral margins of the neural folds in rostral regions of the embryo beginning at stage 15, and is not associated with a more substantial current leak from the blastopore which appears at gastrulation. A steady blastopore current is still present after neural tube formation when intra-embryonic electric fields have been extinguished. We discuss the direct experimental tests supporting the hypothesis that these extracellular electric fields both polarize the early vertebrate embryo and serve as cues for morphogenesis and pattern.
Quantification of Regional Myocardial Perfusion by Exponential Infusion of 11C-Butanol (1983)

This study was designed to determine whether regional myocardial perfusion can be assessed quantitatively in vivo in dogs by administration of a freely diffusible tracer intravenously at an exponentially increasing-rate. Previously, we reported the mathematical basis of the approach and its use for assessment of global perfusion in isolated hearts. In this study, computer simulations demonstrated that inter-regional diffusion of tracer perturbs results by no more than 7 percent under worst case conditions. Regional myocardial blood flow assessed in open chest dogs with myocardial activity deternined by well counting by the exponential infusion method correlated closely to values obtained with radiolabeled microspheres (r = 0.986, n = 35 determinations). Thus, regional myocardial perfusion can be quantified with an infusion technique potentially applicable to the tomographic characterization of impaired perfusion in experimental animals and ultimately in patients with positron emission tomography.
The Catalytic Isomerization of Terminal Carbon–Carbon Double Bonds in Liquid Crystalline Polyesters at Hydrosilation with 1-(1′-Arylethoxy)-1,1,3,3-Tetramethyl Disiloxanes (2006)

In the present article, we report on the synthesis and investigation of the hydrosilylation of liquid crystalline compounds with terminal carbon–carbon double bonds in aliphatic tails mediated by complexes of rhodium (I) and platinum (II). New liquid crystalline compounds based on terephthaloyl-bis-4-oxybenzoate with terminal carbon-carbon double bonds in aliphatic tails were synthesized. The introduction in aliphatic tails of polar and light polarizible fragments lead to a decrease of mesomorphogenic ability-resulting compounds. The hydrosilylation of liquid crystalline compounds with terminal carbon-carbon double bonds in aliphatic tails with 1-(1′-arylethoxy)-1,1,3,3-tetramethyl disiloxanes mediated by complexes of rhodium (I) and platinum (II) was investigated. The main process in these conditions was the isomerization of olefin fragments.
A simple and rapid method for the isolation of human alpha-fetoprotein from human cord serum. (1987)

A description is given of a simple and time-saving method for the isolation of human alpha-fetoprotein (AFP) by means of liquid chromatography. The isolation was made in three steps: Step 1--affinity chromatography on column CNBr-Sepharose 4 B coupled with sheep antibody against human alpha-fetoprotein. AFP was eluted from the column by a change pH. Step 2--application of AFP to column Blue-Sepharose CL-6B for the removal of albumin remnants. Step 3--additional purification of the AFP preparation on column Con-A-Sepharose. AFP was eluted from the column by using methyl-alpha-D-glucepyranoside gradient. The isolation yield was 20%. The purity of the AFP preparation was satisfactory for RIA.
A permanently charged tamoxifen derivative displays anticancer activity and improved tissue selectivity in rodents. (1996)

A quaternized form of tamoxifen (TAM), tamoxifen methiodide (TMI), was shown to demonstrate very low brain uptake compared to TAM and, unexpectedly, was considerably less estrogenic than TAM in the uterus. The agonist activity of TMI in the bone was similar to that of TAM. TMI manifested significant dose-dependent tumoricidal activity with a rapid onset of action against MCF-7 human breast cancer implants in nude mice and a mean reduction in tumor size of 60% over six weeks.
A Transaxial Compression Technique (TACT) for Localized Pulse-Echo Estimation of Sound Speed in Biological Tissues (1990)

We describe a new method for the estimation of the speed of sound in soft tissues in the pulse-echo mode. A transducer imparts an accurate transaxial compression to the tissue, and the corresponding change in the arrival time of an echo feature is measured. The ratio between the compressed depth and the difference in arrival time is taken as the estimate of the speed of sound. A second, noncompressing transducer is used to correct for distal tissue movement. We show theoretically and experimentally that accurate speed of sound estimations can be made in overlying and underlying tissue mimicking layers.
Resistive Switching and Memory effects in Silicon Oxide Based Nanostructures (2011)

Silicon oxide (SiO x 1 ∠ x [∠, double =]2) has long been used and considered as a passive and insulating component in the construction of electronic devices. In contrast, here the active role of SiO x in constructing a type of resistive switching memory is studied. From electrode-independent electrical behaviors to the visualization of the conducting filament inside the SiO x matrix, the intrinsic switching picture in SiO x is gradually revealed. The thesis starts with the introduction of some similar phenomenological switching behaviors in different electronic structures (Chapter 1), and then generalizes the electrode-material-independent electrical behaviors on SiO x substrates, providing indirect evidence to the intrinsic SiO x switching (Chapter 2). From planar nanogap systems to vertical sandwiched structures, Chapter 3 further discusses the switching behaviors and properties in SiO x . By localization of the switching site, the conducting filament in SiO x is visualized under transmission electron microscope using both static and in situ imaging methods (Chapter 4). With the intrinsic conduction and switching in SiO x largely revealed, Chapter 5 discusses its impact and implications to the molecular electronics and nanoelectronics where SiO x is constantly used. As comparison, another type of memory effect in semiconductors (carbon nanotubes) based on charge trapping at the semiconductor/SiO x interface is discussed (Chapter 6).
High-speed BiCMOS operational amplifier for switched-capacitor circuits (2002)

A high-speed fully-differential operational amplifier (op-amp) realized in 2-/spl mu/ BiCMOS technology is proposed. Input MOS buffers allow the use of this op-amp in switched capacitor (SC) circuits with high clock frequency (up to 75 MHz). The gain stage is realized with resistively-loaded bipolar devices. No common mode feedback is required. This saves area and power and increases speed. The op-amp presents a DC gain of about 46 dB with a unity-gain frequency as large as 700 MHz with 1.5 pF load. The measured performance of closed-loop settling time (1%) is about 12 ns.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Portal 5-hydroxytryptophan infusion enhances glucose disposal in conscious dogs (2005)

Intraportal serotonin infusion enhances net hepatic glucose uptake (NHGU) during glucose infusion but blunts nonhepatic glucose uptake and can cause gastrointestinal discomfort and diarrhea at high doses. Whether the serotonin precursor 5-hydroxytryptophan (5-HTP) could enhance NHGU without gastrointestinal side effects during glucose infusion was examined in conscious 42-h-fasted dogs, using arteriovenous difference and tracer ([3-3H]glucose) techniques. Experiments consisted of equilibration (-120 to -30 min), basal (-30 to 0 min), and experimental (EXP; 0-270 min) periods. During EXP, somatostatin, fourfold basal intraportal insulin, basal intraportal glucagon, and peripheral glucose (to double the hepatic glucose load) were infused. In one group of dogs (HTP, n = 6), saline was infused intraportally from 0 to 90 min (P1), and 5-HTP was infused intraportally at 10, 20, and 40 microg x kg(-1) x min(-1) from 90 to 150 (P2), 150 to 210 (P3), and 210 to 270 (P4) min, respectively. In the other group (SAL, n = 7), saline was infused intraportally from 0 to 270 min. NHGU in SAL was 14.8 +/- 1.9, 18.5 +/- 2.3, 16.3 +/- 1.4, and 19.7 +/- 1.6 micromol x kg(-1) x min(-1) in P1-P4, whereas NHGU in 5-HTP averaged 16.4 +/- 2.6, 18.5 +/- 1.4, 20.8 +/- 2.0, and 27.6 +/- 2.6 micromol x kg(-1) x min(-1) (P < 0.05 vs. SAL). Nonhepatic glucose uptake (micromol x kg(-1) x min(-1)) in SAL was 30.2 +/- 4.3, 36.8 +/- 5.8, 44.3 +/- 5.8, and 54.6 +/- 11.8 during P1-P4, respectively, whereas in HTP the corresponding values were 26.3 +/- 6.8, 44.9 +/- 10.1, 47.5 +/- 11.7, and 51.4 +/- 13.2 (not significant between groups). Intraportal 5-HTP enhances NHGU without significantly altering nonhepatic glucose uptake or causing gastrointestinal side effects, raising the possibility that a related agent might have a role in reducing postprandial hyperglycemia.
Synthesis of Enantiopure Sulfonimidamides and Elucidation of Their Absolute Configuration by Comparison of Measured and Calculated CD Spectra and X‐Ray Crystal Structure Determination (2009)

Straightforward syntheses of enantiopure N-benzoyl- and N-tert-butyloxycarbonyl-protected sulfonimidamides, which can be used as building blocks in newly designed catalysts, are presented. Key synthetic step is a dynamic resolution of a racemic sulfinic acid sodium salt. All subsequent transformations proceed stereospecifically. The absolute configurations at the sulfur atoms of both sulfonimidamides were determined by comparison of measured and calculated CD spectra. An X-ray crystal structure determination of a sulfonimidoylguanidine derivative confirmed this result.
Fault tolerant control of electric power steering using robust filter-simulation study (2009)

This paper discusses a fault tolerant control (FTC) design in an electric power steering (EPS) system considering the case of a faulty torsion bar torque sensor. The total torque that acts on the assist motor shaft is the sum of the torsion bar torque and road torque. By estimating the road torque using the vehicle model and signals from the vehicle stability systems and the total torque on the assist motor shaft using a motor model based observer, the torsion bar torque sensor signal can be estimated. The parameter variation is also considered in order to give robust performance in practical case.
Global Static Testing and Model Validation of Stiffened Thin-Film Polyimide Panels (2008)

Covers advancements in spacecraft and tactical and strategic missile systems, including subsystem design and application, mission design and analysis, materials and structures, developments in space sciences, space processing and manufacturing, space operations, and applications of space technologies to other fields.
Delayed Frost Growth on Jumping-Drop Superhydrophobic Surfaces (2013)

Self-propelled jumping drops are continuously removed from a condensing superhydrophobic surface to enable a micrometric steady-state drop size. Here, we report that subcooled condensate on a chilled superhydrophobic surface are able to repeatedly jump off the surface before heterogeneous ice nucleation occurs. Frost still forms on the superhydrophobic surface due to ice nucleation at neighboring edge defects, which eventually spreads over the entire surface via an interdrop frost wave. The growth of this interdrop frost front is shown to be up to 3 times slower on the superhydrophobic surface compared to a control hydrophobic surface, due to the jumping-drop effect dynamically minimizing the average drop size and surface coverage of the condensate. A simple scaling model is developed to relate the success and speed of interdrop ice bridging to the drop size distribution. While other reports of condensation frosting on superhydrophobic surfaces have focused exclusively on liquid-solid ice nucleation for isolated drops, these findings reveal that the growth of frost is an interdrop phenomenon that is strongly coupled to the wettability and drop size distribution of the surface. A jumping-drop superhydrophobic condenser minimized frost formation relative to a conventional dropwise condenser in two respects: preventing heterogeneous ice nucleation by continuously removing subcooled condensate, and delaying frost growth by limiting the success of interdrop ice bridge formation.
Facile preparation of water-soluble fluorescent silver nanoclusters using a polyelectrolyte template (2008)

We report a new approach for the synthesis of fluorescent and water-soluble Ag nanoclusters, using the common polyelectrolyte poly(methacrylic acid) as the template.
Cryopreservation of Human Semen (1990)

A review is given of the techniques for the cryopreservation of human semen, including the preparation of cryoprotective media, the use of ampoules, straws, and pellets, and freezing and thawing techniques. The use of cryopreserved semen for therapeutic artificial insemination by donor is described. The advantages of cryopreserved semen over fresh donor semen mostly lie in the ability to exclude infections before use and the extra convenience, in spite of the lower success rate and increased cost. The recovery of sperm motility on thawing is described, as are other methods for assessing the degree of damage to the spermatozoa by the freezing procedure. The success rates reported by large semen banks are summarized.
The neurofibromatoses. Part 2: NF2 and schwannomatosis. (2009)

The neurofibromatoses, including neurofibromatosis 1 (NF1), neurofibromatosis 2 (NF2), and schwannomatosis, comprise a group of genetically distinct disorders of the nervous system that are unified by the predisposition to nerve sheath tumors. All 3 types of NF have tumor manifestations (consistent with tumor-suppressor status) and nontumor manifestations. In the second part of this 2-part series, the manifestations of NF2 and schwannomatosis are reviewed. NF2 is characterized by bilateral vestibular schwannomas, meningiomas, ependymomas, cataracts, and epiretinal membranes. The combination of complete hearing loss from vestibular schwannomas and blindness from bifacial weakness is a devastating potential outcome of NF2. Schwannomatosis is characterized by multiple nonvestibular, nonintradermal schwannomas and chronic pain. Recently, germline alterations in the SMARCB1/INI1 gene have been implicated in both familial and sporadic forms of this disorder. Neurologists play an important role in the diagnosis and management of the neurofibromatoses.
Size-dependent predilections of cardiogenic embolic transport (2013)

While it is intuitively clear that aortic anatomy and embolus size could be important determinants for cardiogenic embolic stroke risk and stroke location, few data exist confirming or characterizing this hypothesis. The objective of this study is to use medical imaging and computational modeling to better understand if aortic anatomy and embolus size influence predilections for cardiogenic embolic transport and right vs. left hemisphere propensity. Anatomically accurate models of the human aorta and branch arteries to the head were reconstructed from computed tomography (CT) angiography of 10 patients. Blood flow was modeled by the Navier-Stokes equations using a well-validated flow solver with physiologic inflow and boundary conditions. Embolic particulate was released from the aortic root and tracked through the common carotid and vertebral arteries for a range of particle sizes. Cardiogenic emboli reaching the carotid and vertebral arteries appeared to have a strong size-destination relationship that varied markedly from expectations based on blood distribution. Observed trends were robust to modeling parameters. A patient's aortic anatomy appeared to significantly influence the probability a cardiogenic particle becomes embolic to the head. Right hemisphere propensity appeared dominant for cardiogenic emboli, which has been confirmed clinically. The predilections discovered through this modeling could represent an important mechanism underlying cardiogenic embolic stroke etiology.
Substrate specificity of cholylglycine hydrolase for the hydrolysis of bile acid conjugates. (1984)

The substrate specificity of cholylglycine hydrolase has been investigated using bile acid conjugates with modifications in the steroid ring system, the side chain, or the amino acid moiety. Epimerization at C-3 and C-7 did not affect the activity of the enzyme while oxidation of the three nuclear hydroxyl groups reduced the affinity of the enzyme toward the substrate. Elongation of the side chain by one or three carbons inhibited enzyme activity. Conjugates prepared from C24 bile acids and analogs of taurine and glycine with one or two methylene groups were effectively hydrolyzed, whereas conjugates with a tertiary amide group completely resisted hydrolysis. Increasing the length of the bile acid side chain or using a bile acid conjugate with a tertiary amide group may produce compounds that will resist intestinal bacterial destruction.
Arsenic Adsorption by Fe(III)-Loaded Open-Celled Cellulose Sponge. Thermodynamic and Selectivity Aspects (2002)

Nowadays there is a great concern on the study of new adsorbent materials for either the removal or fixation of arsenic species because of their high toxicity and the health problems associated to such substances. The present paper reports a basic study of the adsorption of arsenic inorganic species from aqueous solutions using an open-celled cellulose sponge with anion-exchange and chelating properties (Forager Sponge). Consequences of preloading the adsorbentwith Fe(III) to enhance the adsorption selectivity are discussed and compared with the nonloaded adsorbent properties. The interactions of arsenic species with the Fe(III)-loaded adsorbent are accurately determined to clarify the feasibility of an effective remediation of contaminated waters. Arsenate is effectively adsorbed by the nonloaded and the Fe(III)-loaded sponge in the pH range 2-9 (maximum at pH 7), whereas arsenite is only slightly adsorbed by the Fe(III)-loaded sponge in the pH range 5-10 (maximum at pH 9), being that the nonloaded sponge is unable to adsorb As(III). The maximum sorption capacities are 1.83 mmol As(V)/g (pH approximately 4.5) and 0.24 mmol As(lII)/g (pH approximately 9.0) for the Fe(III)-loaded adsorbent. This difference is explained in terms of the different acidic behavior of both arsenic species. The interaction of the arsenic species with the Fe(III) loaded in the sponge is satisfactorily modeled. A 1:1 Fe:As complex is found to be formed for both species. H2AsO4- and H3AsO3 are determined to be adsorbed on Fe(III) with a thermodynamic affinity defined by log K = 2.5 +/- 0.3 and log K = 0.53 +/- 0.07, respectively. As(V) is, thus, found to be more strongly adsorbed than As(III) on the Fe(III) loaded in the sponge. A significant enhancement on As(V) adsorption selectivity by loading Fe(III) in the sponge is observed, and the effectiveness of the Fe(III)-loaded sponge for the As(V) adsorption is demonstrated, even in the presence of high concentrations of interfering anions (chloride, nitrate, sulfate, and phosphate).
Expression of the Na-Ca exchanger in diverse tissues: a study using the cloned human cardiac Na-Ca exchanger (1992)

In many cells including cardiac myocytes, cytoplasmic Ca is importantly controlled by the plasmalemmal Na-Ca exchanger (3, 8). The tissue diversity and differences in cellular environment raise the question whether the same exchanger is found in all tissues. Recent experiments using rod cells have demonstrated that at least two forms of Na-dependent Ca transport exist. We have examined this issue in various rat and human tissues using the cloned human cardiac Na-Ca exchanger cDNA. Northern blot analysis in these two species show that the major transcript of the Na-Ca exchanger is 7.2 kilobases in heart, brain, kidney, liver, pancreas, skeletal muscle, placenta, and lung. Furthermore, ribonuclease protection analysis in rats shows conservation of the 348-base pair segment tested in heart, brain, kidney, skeletal muscle, and liver. Additionally, Southern blot analysis suggests that a single gene encodes this Na-Ca exchanger. Finally, we show that the clone used to generate our probes encodes a completely functional Na-Ca exchanger. With the use of COS cells and 293 cells transfected with the cloned human cardiac Na-Ca exchanger, we tested the Ca transport properties of the Na-Ca exchanger, the voltage dependence of the Na-Ca exchanger, as well as the Na dependence of the transport function of the Na-Ca exchanger. We conclude that the cardiac form of the Na-Ca exchanger is completely functional when the cDNA is expressed in mammalian cell lines, and, furthermore, this "cardiac" form of the Na-Ca exchanger is naturally expressed in all human and rat tissues tested (but at varying levels).