gebhart/patrepeval huggingface dataset:
In Situ Formed “Weakly Ligated/Labile Ligand” Iridium(0) Nanoparticles and Aggregates as Catalysts for the Complete Hydrogenation of Neat Benzene at Room Temperature and Mild Pressures (2010)

"Weakly ligated/labile ligand" nanoparticles, that is nanoparticles where only weakly coordinated ligands plus the desired catalytic reactants are present, are of fundamental interest. Described herein is a catalyst system for benzene hydrogenation to cyclohexane consisting of "weakly ligated/labile ligand" Ir(0) nanoparticles and aggregates plus dry-HCl formed in situ from commercially available [(1,5-COD)IrCl](2) plus 40 +/- 1 psig (approximately 2.7 atm) H(2) at 22 +/- 0.1 degrees C. Multiple control and other experiments reveal the following points: (i) that this catalyst system is quite active with a TOF (turnover frequency) of 25 h(-1) and TTO (total turnovers) of 5250; (ii) that the BF(4)(-) and PF(6)(-) iridium salt precursors, [(1,5-COD)Ir(CH(3)CN)(2)]BF(4) and [(1,5-COD)Ir(CH(3)CN)(2)]PF(6), yield inferior catalysts; (iii) that iridium black with or without added, preformed HCl cannot achieve the TOF of 25 h(-1) of the in situ formed Ir(0)/dry-HCl catalyst. However and importantly, CS(2) poisoning experiments yield the same activity per active iridium atom for both the Ir(0)/dry-HCl and Ir black/no-HCl catalysts (12.5 h(-1) Ir(1-)), but reveal that the Ir(0)/dry-HCl system is 10-fold more dispersed compared to the Ir(0) black catalyst. The simple but important and key result is that "weakly ligated/labile ligand" Ir(0) nanoparticles and aggregates have been made in situ as demonstrated by the fact that they have identical, per exposed Ir(0) activity within experimental error to Ir(0) black and that they have no possible ligands other than those desired for the catalysis (benzene and H(2)) plus the at best poor ligand HCl. As expected, the in situ catalyst is poorly stabilized, exhibiting only 60% of its initial activity in a second run of benzene hydrogenation and resulting in bulk metal precipitation. However, stabilization of the Ir(0) nanoparticles with a ca. 2-fold higher catalytic activity and somewhat longer lifetime for the complete hydrogenation of benzene was accomplished by supporting the Ir(0) nanoparticles onto zeolite-Y (TOF of 47 h(-1) and 8600 TTO under otherwise identical conditions). Also reported is the interesting result that Cl(-) (present as Proton Sponge x H(+)Cl(-)) completely poisons benzene hydrogenation catalysis, but not the easier cyclohexene hydrogenation catalysis under otherwise the same conditions, results that suggest different active sites for these ostensibly related hydrogenation reaction. The results suggest that synthetic routes to "weakly ligated/labile ligand" nanoparticles exhibiting improved catalytic performance is an important goal worthy of additional effort.
Oxidative degradation of an antitumor (1-3)-.BETA.-D-glucan, grifolan. (1991)

A (1-3)-beta-D-glucan, grifolan (GRN), recovered from the peritoneal cavity after 1 d from i.p. injection contained a significant amount of anionic metabolite(s) having lower Mr than the parent GRN. In parallel with this observation, GRN induced peritoneal exudate cells exhibiting a higher level of oxidative burst than the non-stimulated, resident peritoneal cells. Chemical oxidation of GRN by active oxygen species such as (a) ascorbic acid-CuSO4, (b) hydrogen peroxide, (c) hydrogen peroxide-CuSO4, or (d) hypochlorous acid also produced anionic as well as lower Mr degradation products. Under these experimental conditions the structural changes were remarkable and in the order of a less than b less than c less than d. The products formed under the conditions (a) and (b) retained significant antitumor activity but those of (c) and (d) lost the activity. However, oxidation product(s) of curdlan, an antitumor inactive (1-3)-beta-D-glucan having no branch, by condition (d) induced significant antitumor activity. These results suggested that oxidative degradation of (1-3)-beta-D-glucans produced some temporary active metabolites and then gradually changed to the inactive form. However, these active metabolites contribute less than the parent glucan on the whole activation mechanisms of the host by (1-3)-beta-D-glucans.
Aggregation of RANTES Is Responsible for Its Inflammatory Properties (1999)

The biology of RANTES (regulated on activation normal T cell expressed) aggregation has been investigated using RANTES and disaggregated variants, enabling comparison of aggregated, tetrameric, and dimeric RANTES forms. Disaggregated variants retain their G(i)-type G protein-coupled receptor-mediated biological activities. A correlation between RANTES aggregation and cellular activation has been demonstrated. Aggregated RANTES, but not disaggregated RANTES, activates human T cells, monocytes, and neutrophils. Dimeric RANTES has lost its cellular activating activity, rendering it noninflammatory. Macrophage inflammatory protein 1alpha, macrophage inflammatory protein-1beta, and erythrocytes are potent natural antagonists of aggregated RANTES-induced cellular activation. There is a clear difference in the signaling properties of aggregated and disaggregated RANTES forms, separating the dual signaling pathways of RANTES and the enhancing and suppressive effects of RANTES on human immunodeficiency virus infection. Disaggregated RANTES will be a valuable tool to explore the biology of RANTES action in human immunodeficiency virus infection and in inflammatory disease.
Fertility Therapies, Infertility and Autism Spectrum Disorders in the Nurses' Health Study II (2012)

[corrected] Assisted reproductive therapy and history of infertility did not increase risk of having a child with ASD in this study. However, the associations observed with OID and artificial insemination among older mothers, for whom these exposures are more common, warrant further investigation.
Carcinoembryonic antigen levels in peritoneal washings can predict peritoneal recurrence after curative resection of gastric cancer (1991)

Carcinoembryonic antigen (CEA) levels were determined in the peritoneal washings from 120 patients with gastric cancer and 9 patients with benign diseases. Elevated values (greater than 100 ng/g of protein) were observed in 20 of 25 patients with gastric cancer with visible dissemination and 16 of 25 patients with serosal invasion but no dissemination. The same elevation was found in only 9 of 70 patients with no serosal invasion and none of the patients with benign disease. The 2-year survival rates after curative operation for the patients with and without elevation of CEA levels were 21% (19 patients) and 100% (66 patients), respectively (P less than 0.001). A negative correlation was found between CEA levels and survival times after noncurative operation. These results indicate that the CEA level in peritoneal washings could be a sensitive detector of invisible peritoneal dissemination and a new predictor for the postoperative prognosis of gastric cancer.
Vapor Hydrofluoric Acid Sacrificial Release Technique for Micro Electro Mechanical Systems Using Labware (2003)

We have developed a novel technique of sacrificial layer etching for micro electro mechanical systems (MEMS). Our technique uses vapor of hydrofluoric acid (HF) to etch sacrificial silicon oxide and to make freestanding silicon microstructures. The advantages of this technique are: (1) no subsequent water rinse is needed, (2) freestanding silicon microstructures can be successfully released without sticking to the substrate, (3) equipment for our vapor phase HF etching simply consists of Teflon beakers only. Conditions for the technique have been optimized by estimating etching rate with test patterns made of silicon-on-insulator (SOI) wafers and by observing water droplets condensation on the sample surface with thermally oxidized silicon chips. By this technique we have successfully obtained freestanding microstructures of SOI wafers. Microcantilevers of as long as 5000 µm (a 5-µm-wide, 10-µm-thick, and 5000-µm-long cantilever over a 0.6-µm-gap) have been successfully released without adhering to the base substrate or contacting the neighboring cantilevers. We have also fabricated and actuated electrostatic comb-drive actuators of 60 and 200 comb pairs to demonstrate high processing yield of our nonstick releasing technique.
Magnetic fields from simulated cardiac action currents (1994)

A digital simulation has been performed of an idealized, thin, 2-D cardiac slice in the chi-y plane. The slice is stimulated near the center and the resulting action potential propagates outward, developing a distribution of electrical current with nonzero curl. An anisotropic bidomain model is used for the calculation, with membrane physiology based upon either just fast sodium fluxes or the more complete Beeler-Reuter myocardial model. The electrical anisotropy, expressed as the ratio of longitudinal to transverse electrical conductivity, is much greater for the inner domain than for the outer one, and this results in current loops that develop ahead of and behind the wavefront and produce a Bz magnetic field of order 10(-9) T 1 mm above the tissue, similar to recent experimental observations on canine cardiac tissue slices. The fields exhibit a quatrefoil symmetry which can be distorted by nonuniformities in the tissue. The field from repolarization currents is larger by almost an order of magnitude than might be predicted from considerations of rate of change of voltage.
A Rapid, Accurate, and Efficient Method to Map Heavy Metal-Contaminated Soils of Abandoned Mine Sites Using Converted Portable XRF Data and GIS (2016)

The use of portable X-ray fluorescence (PXRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES) increases the rapidity and accuracy of soil contamination mapping, respectively. In practice, it is often necessary to repeat the soil contamination assessment and mapping procedure several times during soil management within a limited budget. In this study, we have developed a rapid, inexpensive, and accurate soil contamination mapping method using a PXRF data and geostatistical spatial interpolation. To obtain a large quantity of high quality data for interpolation, in situ PXRF data analyzed at 40 points were transformed to converted PXRF data using the correlation between PXRF and ICP-AES data. The method was applied to an abandoned mine site in Korea to generate a soil contamination map for copper and was validated for investigation speed and prediction accuracy. As a result, regions that required soil remediation were identified. Our method significantly shortened the time required for mapping compared to the conventional mapping method and provided copper concentration estimates with high accuracy similar to those measured by ICP-AES. Therefore, our method is an effective way of mapping soil contamination if we consistently construct a database based on the correlation between PXRF and ICP-AES data.
PCR-SSCP:  A Simple Method for the Authentication of Grouper (<i>Epinephelus guaza</i>), Wreck Fish (<i>Polyprion americanus</i>), and Nile Perch (<i>Lates niloticus</i>) Fillets (2001)

A method of DNA analysis has been developed to verify the authenticity of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. A short fragment (208 bp) of the mitochondrial 12S rRNA gene was amplified by the polymerase chain reaction and analyzed by single-strand conformation polymorphism to get species-specific patterns of single-stranded DNA (ssDNA). DNA strands were separated by native polyacrylamide gel electrophoresis and visualized by silver staining. Discrimination among the three fish species studied was possible, because each one expressed a specific ssDNA pattern.
Channel length and width effects on NMOS transistor degradation under constant positive gate-voltage stressing (2002)

It is pointed out that a reliable gate oxide is the most important component for MOS devices operating under a high gate voltage. Trapped charges and interface states are generated in the oxide under a high gate-voltage bias due to Fowler-Nordheim tunneling. The gate current, charge pumping current, and threshold voltage shift critically depend on the electric field across gate oxide. It is demonstrated that device degradation is a strong function of channel width to channel length ratio (W/L). Under the same stress condition, a higher W/L ratio leads to more severe degradation. This geometric effect is the result of nonuniform distribution of trapped charges and interface states. The densities of trapped charges and the interface states are highest near the source and drain regions and lowest along the isolation edges.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A High-Bandwidth Force-Controlled Haptic Interface (2000)

Abstract The design and control of a 5 degree-of-freedom (DOF) haptic interface that provides accurate rendering of forces as well as a large range of motion is presented. We review a number of design approaches that have been considered in other haptic interfaces and the reasons for choosing a parallel mechanism for our design. The choice and motivation for the actuators, sensors, and materials used are also discussed. High bandwidth transmission of forces is achieved through a force control loop in each degree of freedom. Details of the single actuator control design process and the robustness of the controllers are also overviewed. The resulting interface is able to provide a workspace of about 40 cm in translation in 3 DOF and about ±60 degrees in 2 DOF of angular motion, and the force controllers have closed-loop bandwidths of about 175 Hz.
Soluble Prion Protein Inhibits Amyloid-β (Aβ) Fibrillization and Toxicity (2012)

The pathogenesis of Alzheimer disease appears to be strongly linked to the aggregation of amyloid-β (Aβ) peptide and, especially, formation of soluble Aβ1-42 oligomers. It was recently demonstrated that the cellular prion protein, PrP(C), binds with high affinity to these oligomers, acting as a putative receptor that mediates at least some of their neurotoxic effects. Here we show that the soluble (i.e. glycophosphatidylinositol anchor-free) prion protein and its N-terminal fragment have a strong effect on the aggregation pathway of Aβ1-42, inhibiting its assembly into amyloid fibrils. Furthermore, the prion protein prevents formation of spherical oligomers that normally occur during Aβ fibrillogenesis, acting as a potent inhibitor of Aβ1-42 toxicity as assessed in experiments with neuronal cell culture. These findings may provide a molecular level foundation to explain the reported protective action of the physiologically released N-terminal N1 fragment of PrP(C) against Aβ neurotoxicity. They also suggest a novel approach to pharmacological intervention in Alzheimer disease.
Physiological Regulation of Magnocellular Neurosecretory Cell Activity: Integration of Intrinsic, Local and Afferent Mechanisms (2013)

The hypothalamic supraoptic and paraventricular nuclei contain magnocellular neurosecretory cells (MNCs) that project to the posterior pituitary gland where they secrete either oxytocin or vasopressin (the antidiuretic hormone) into the circulation. Oxytocin is important for delivery at birth and is essential for milk ejection during suckling. Vasopressin primarily promotes water reabsorption in the kidney to maintain body fluid balance, but also increases vasoconstriction. The profile of oxytocin and vasopressin secretion is principally determined by the pattern of action potentials initiated at the cell bodies. Although it has long been known that the activity of MNCs depends upon afferent inputs that relay information on reproductive, osmotic and cardiovascular status, it has recently become clear that activity depends critically on local regulation by glial cells, as well as intrinsic regulation by the MNCs themselves. Here, we provide an overview of recent advances in our understanding of how intrinsic and local extrinsic mechanisms integrate with afferent inputs to generate appropriate physiological regulation of oxytocin and vasopressin MNC activity.
A new technique for dynamic gain profile control in a multi-wavelength backward-pumped discrete Raman amplifier (2006)

We propose and experimentally verify a new dynamic gain profile control technique for a multi-wavelength backward-pumped discrete Raman amplifier without using a channel monitor. We demonstrate up to 9 dB static power correction and a dynamic implementation.
Optical properties and infrared optics applications of composite films based on polyethylene and low-melting-point chalcogenide glass (2002)

A novel composite material based on medium-density poly- ethylene and thermoplastic chalcogenide glass has been produced. Both materials are highly transparent in the middle and far IR, but their refrac- tive indices differ dramatically. The polymer and the glass have nearly equal viscosities at the temperature of polyethylene processing. This fact allowed the use of extrusion for homogenization. Single- and twin-screw extrusion processes yielded compositions that contain up to 40% of chal- cogenide glass particles, which were dispersed in the polymer matrix. Highly homogeneous compositions that contain perfectly spherical glass particles 1 to 2 mm in diameter dispersed in the polymer matrix were obtained. Highly oriented structures involving chalcogenide glass fibers immersed in the polymer matrix were prepared at high stretch speeds. It was established that it is possible to produce a composite that is opaque in the visible and near IR, and highly transparent in the 2 to 25-mm wavelength band. The use of oriented films as IR laser light-shaping diffusers is possible. The composite films obtained were tried success- fully as immersion adhesive layers for the contacting of IR fibers. © 2002
TREM2 Function in Alzheimer’s Disease and Neurodegeneration (2016)

Alzheimer's disease (AD), the most common cause of dementia in the elderly, is a complex neurodegenerative disease marked by the appearance of amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles. Alzheimer's disease has a strong genetic component, and recent advances in genome technology have unearthed novel variants in several genes, which could provide insight into the pathogenic mechanisms that contribute to AD. Particularly interesting are variants in the microglial-expressed receptor TREM2 which are associated with a 2-4-fold increased risk of developing AD. Since the discovery of a link between TREM2 and AD, multiple studies have emerged testing whether partial or complete loss of TREM2 function contributed to Aβ deposition or Aβ-associated microgliosis. Although some confounding conflicting data have emerged from these studies regarding the role of TREM2 in regulating Aβ deposition within the hippocampus, the most consistent and striking observation is a strong decrease in microgliosis surrounding Aβ plaques in TREM2 haploinsufficient and TREM2 deficient mice. Interestingly, a similar impairment in microgliosis has been reported in mouse models of prion disease, stroke, and multiple sclerosis, suggesting a critical role for TREM2 in supporting microgliosis in response to pathology in the central nervous system. In this Review, we summarize recent reports on the role of TREM2 in AD pathology and hypothesized mechanisms by which TREM2 function could influence AD-induced microgliosis.
A BOUNDARY METHOD FOR ATTENUATION CORRECTION IN POSITRON COMPUTED TOMOGRAPHY (1981)

A new method for attenuation correction in positron computed tomography (PCT) has been developed, and it can improve the quality of PCT images. The method requires a short transmission scan by the PCT system. Then boundaries between tissues with significantly different attenuation coefficients are determined from the transmission image by edge-finding techniques. Attenuation correction factors(ACF) are then calculated using these boundaries and the average attenuation coefficients within the enclosed regions. The method has been tested on computer-simulated data, on scans of phantoms, and on patient studies, and has been found effective in reducing the random noise in transmission measurements and in providing more accurate ACFs than the method using geometric attenuation correction. As a result, transmission scan times can be shortened, inconvenience to patients is reduced, and PCT images are improved.
Does "Blastocyst Estrogen" Initiate Implantation? (1977)

Fertilized eggs were incubated for 2 hours in a medium containing estradiol-17beta and then transferred into the uteri of day 5 pseudopregnant rats. These eggs, but not estrogen-free control eggs, induced a local increase in capillary permeability. We suggest that the blastocyst factor which induces the local increase in capillary permeability during early pregnancy is estrogen synthesized by the blastocyst.
Corn Yield Response to Nitrogen Fertilizer Timing and Deficiency Level (2002)

Nitrogen fertilizer is typically applied to corn ( Zea mays L.) shortly before planting, but there are several reasons why later N applications may be of interest: to spread work away from the busy planting season, to avoid the frequent wet field conditions in spring, to reduce or remedy in‐season N loss in wet years, or to allow use of in‐season diagnostic tools. One of the obstacles to the use of later N applications is the fear that irreversible yield loss will occur due to N stress. Our objective was to evaluate the yield impact of delaying N applications until the late vegetative growth stages and as far as silking. We conducted a total of 28 experiments with timing of a single N application as the experimental treatment. We found little or no evidence of irreversible yield loss when N applications were delayed as late as stage V11, even when N stress was highly visible. There was weak evidence of minor yield loss (about 3%) when N applications were delayed until stage V12 to V16. Only 3 of the 28 experiments had N applications later than V16—all were at silking and relative yields were 0.71, 0.89, and 0.95. Though full yield was not achieved when N applications were delayed until silking, yield was still highly responsive to N application at this stage—yield response exceeded 2.2 Mg ha −1 in all three experiments.