gebhart/patrepeval huggingface dataset:
A review of dry (CO<sub>2</sub>) reforming of methane over noble metal catalysts (2014)

Dry (CO2) reforming of methane (DRM) is a well-studied reaction that is of both scientific and industrial importance. This reaction produces syngas that can be used to produce a wide range of products, such as higher alkanes and oxygenates by means of Fischer-Tropsch synthesis. DRM is inevitably accompanied by deactivation due to carbon deposition. DRM is also a highly endothermic reaction and requires operating temperatures of 800-1000 °C to attain high equilibrium conversion of CH4 and CO2 to H2 and CO and to minimize the thermodynamic driving force for carbon deposition. The most widely used catalysts for DRM are based on Ni. However, many of these catalysts undergo severe deactivation due to carbon deposition. Noble metals have also been studied and are typically found to be much more resistant to carbon deposition than Ni catalysts, but are generally uneconomical. Noble metals can also be used to promote the Ni catalysts in order to increase their resistance to deactivation. In order to design catalysts that minimize deactivation, it is necessary to understand the elementary steps involved in the activation and conversion of CH4 and CO2. This review will cover DRM literature for catalysts based on Rh, Ru, Pt, and Pd metals. This includes the effect of these noble metals on the kinetics, mechanism and deactivation of these catalysts.
Graphene-like silicon nanoribbons on Ag(110): A possible formation of silicene (2010)

Scanning tunneling microscopy (STM) and ab initio calculations based on density functional theory (DFT) were used to study the self-aligned silicon nanoribbons on Ag(110) with honeycomb, graphene-like structure. The silicon honeycombs structure on top of the silver substrate is clearly observed by STM, while the DFT calculations confirm that the Si atoms adopt spontaneously this new silicon structure.
Bi‐Functional Oxygen Electrode Using Large Surface Area La1 − x Ca x CoO3 for Rechargeable Metal‐Air Battery (1990)

In order to develop an air electrode to be used for rechargeable metal‐air batteries, gas‐diffusion type carbon‐based electrodes have been tested for the electrochemical reduction and evolution of oxygen. The electrode, loaded with a large surface area of catalyst was found to show high bifunctional performance, i.e., 3000 mA/cm2 (oxygen reduction) and 1000 mA/cm2 (oxygen evolution) at −125 and +700 mV vs. , respectively, in 30 w/o at 25°C. The oxide catalyst is considered to decompose effectively , an intermediate appearing in both oxygen reduction and oxygen evolution reactions. The air electrode was stable for 100 cycles of charge‐discharge test at a current density of 100 mA/cm2.
High-Efficiency Power Amplifier for Wireless Sensor Networks (2005)

We designed a high-efficiency class-E switched-mode power amplifier for a wireless networked micro-sensor system. In this system, where each sensor operates using a micro-battery, has local processing capability, and contains on the same chip integrated sensing elements and an RF transmitter, most of the power is dissipated by the transmitter. The proposed amplifier achieves 92.4% maximum drain efficiency and can vary the transmitted power between -4.2 to -0.2 dBm with almost constant efficiency. This last feature is obtained by controlling the modulation duty cycle and by switching the capacitors' values in the parallel circuit. The possibility of choosing the transmitted power depending on the distance from a base station or other sensors and on the charge level of the battery, combined with power aware network protocols, improves network lifetime, reliability, and adaptability. The amplifier is designed in 0.18 /spl mu/m CMOS process and operates with a nominal 1.2 V supply.
Analysis of Linux Random Number Generator in Virtualized Environment (2015)

With the growing influence of virtualization technologies in modern computing environments, the importance of random number generation in virtualized platforms cannot be ignored. Virtualization offers many advantages like flexibility, cost effectiveness and scalability. Isolation between the host and the guest is one of the main characteristics of virtualization and helps in mitigating attacks on the host through the guest. In this thesis we did a formal study of isolation between the host and the guest in terms of random number generation process. We first did a performance analysis of random number generation system in virtual environment by measuring the rate of random numbers generated from /dev/random interface of Linux RNG. Rate of random number generation refers to the number of random bits generated per unit time. Our measurements showed that emulated softwares do not act as a good source of entropy. We also showed that there is a significant amount of entropy flow from the guest to the host. Our measurements also show that the rate of random number generation of the underlying host is always greater than the guests. Secondly, we formalized the isolation between the guest and the host and developed a jiffy model of Linux RNG analogous to the original Linux RNG. We designed a high disk activity experiment and formulated a prediction strategy, which is used to guess the inputs to the host entropy pool based on the information obtained from the guest. We show that the isolation between the host and the guest does not exist for the jiffy model and an attacker can guess the host input sequences with a better success probability than what is estimated by the Linux entropy estimator. Our study also shows that CPU cycles add a significant amount of entropy to Linux RNG, but is not estimated anywhere.
Synthesis of Mesoporous Silicas of Controlled Pore Wall Thickness and Their Replication to Ordered Nanoporous Carbons with Various Pore Diameters (2002)

A synthesis strategy for the systematic control of the pore wall thickness has been developed for the mesoporous silicas with 2-D hexagonal order using ionic and nonionic surfactant mixtures. The mesoporous silicas have been used as templates for the synthesis of 2-D hexagonally ordered mesoporous carbons with controlled pore diameters. The synthesis strategy and results are useful not only for tailoring the properties of the mesoporous materials but also for extending our insights into the synthesis mechanism.
Accuracy of Contrast-Enhanced Magnetic Resonance Imaging in Predicting Improvement of Regional Myocardial Function in Patients After Acute Myocardial Infarction (2002)

Background— Contrast-enhanced (CE) MRI demonstrates a pattern of hypoenhancement early after contrast injection in acute myocardial infarction (MI) and a pattern of hyperenhancement late after contrast injection. Because the significance of these CE patterns for myocardial viability remains debated, we evaluated their diagnostic accuracy to quantitatively predict late functional improvement of regional contractility. Methods and Results— Twenty patients underwent CE and tagged MRI at 4 days and again at 7 months after acute MI. Resting circumferential shortening strain (Ecc) was analyzed in 24 segments per patient, and its improvement was correlated with the presence or absence of the CE patterns. Immediately after MI, 389 segments were considered dysfunctional because of having less than mean±2 SD Ecc of the remote region (−18±4%). At follow-up, significant improvement of Ecc occurred in 170 dysfunctional segments with normal CE (from −4±7% to −12±7%, P <0.001) but not in 60 segments with early hypoenhancement (from −2±6% to −6±9% Ecc, P =NS). In 240 dysfunctional segments with delayed hyperenhancement, the improvement of Ecc (from −2±6% to −5±8%, P <0.001) decreased with increasing transmural extent of hyperenhancement. Receiver operating characteristic analysis demonstrated that absence of delayed hyperenhancement, compared with absence of early hypoenhancement, had better sensitivity (82% versus 19%, respectively; P <0.001) and accuracy (74% versus 49%, respectively; P <0.001) in predicting recovery of Ecc to any given level. Conclusions— Compared with lack of early hypoenhancement, lack of delayed hyperenhancement has better diagnostic accuracy in predicting functional improvement in dysfunctional segments. The early hypoenhanced regions, which represent only the fraction of infarcted tissue with concomitant microvascular obstruction, greatly underestimate the amount of irreversibly injured myocardium present after acute MI.
In-Situ monitoring and modeling of metal additive manufacturing powder bed fusion (2018)

One of the major challenges in metal additive manufacturing is developing in-situ sensing and feedback control capabilities to eliminate build errors and allow qualified part creation without the need for costly and destructive external testing. Previously, many groups have focused on high fidelity numerical modeling and true temperature thermal imaging systems. These approaches require large computational resources or costly hardware that requires complex calibration and are difficult to integrate into commercial systems. In addition, due to the rapid change in the state of the material as well as its surface properties, getting true temperature is complicated and difficult. Here, we describe a different approach where we implement a low cost thermal imaging solution allowing for relative temperature measurements sufficient for detecting unwanted process variability. We match this with a faster than real time qualitative model that allows the process to be rapidly modeled during the build. The hope is to combine these two, allowing for the detection of anomalies in real time, enabling corrective action to potentially be taken, or parts to be stopped immediately after the error, saving material and time. Here we describe our sensor setup, its costs and abilities. We also show the ability to detect in real time unwanted process deviations. We also show that the output of our high speed model agrees qualitatively with experimental results. These results lay the groundwork for our vision of an integrated feedback and control scheme that combines low cost, easy to use sensors and fast modeling for process deviation monitoring.
Development of the Facial Recess: Implications for Cochlear Implantation (1996)

More attention is being focused on the growth and development of the facial recess because of the use of cochlear implantation in children over 2 years of age and the prospect of using implants in even younger children. The facial recess and the extended facial recess were measured in 123 temporal bones from 73 individuals ranging in age from 8 weeks in utero to 7 years after birth. The goals were to trace the development of the facial recess and to determine whether this area continues to grow into childhood. The facial recess enlarges throughout fetal life with the development of the facial canal and the tympanic annulus. Reichert's cartilage, seen early in utero in the facial recess, gradually resorbs but may persist in the newborn. In full-term infants, the facial recess reaches 3.25 mm at the oval window and 2.62 mm at the round window. The extended facial recess reaches 3.79 mm at the oval window and 3.04 mm at the round window. No statistically significant growth of the facial recess after birth could be demonstrated in this study. The data suggest that the facial recess is probably adult sized at birth and should allow surgical access for cochlear implantation in very young children.
The role of BK‐type Ca<sup>2+</sup>‐dependent K<sup>+</sup>channels in spike broadening during repetitive firing in rat hippocampal pyramidal cells (1999)

1. The role of large-conductance Ca2+-dependent K+ channels (BK-channels; also known as maxi-K- or slo-channels) in spike broadening during repetitive firing was studied in CA1 pyramidal cells, using sharp electrode intracellular recordings in rat hippocampal slices, and computer modelling. 2. Trains of action potentials elicited by depolarizing current pulses showed a progressive, frequency-dependent spike broadening, reflecting a reduced rate of repolarization. During a 50 ms long 5 spike train, the spike duration increased by 63.6 +/- 3.4 % from the 1st to the 3rd spike. The amplitude of the fast after-hyperpolarization (fAHP) also rapidly declined during each train. 3. Suppression of BK-channel activity with (a) the selective BK-channel blocker iberiotoxin (IbTX, 60 nM), (b) the non-peptidergic BK-channel blocker paxilline (2-10 microM), or (c) calcium-free medium, broadened the 1st spike to a similar degree ( approximately 60 %). BK-channel suppression also caused a similar change in spike waveform as observed during repetitive firing, and eliminated (occluded) most of the spike broadening during repetitive firing. 4. Computer simulations using a reduced compartmental model with transient BK-channel current and 10 other active ionic currents, produced an activity-dependent spike broadening that was strongly reduced when the BK-channel inactivation mechanism was removed. 5. These results, which are supported by recent voltage-clamp data, strongly suggest that in CA1 pyramidal cells, fast inactivation of a transient BK-channel current (ICT), substantially contributes to frequency-dependent spike broadening during repetitive firing.
A fast and efficient heuristic algorithm for the delay- and delay variation bound multicast tree problem (2002)

More and more multicast communications are becoming real-time. In real-time communications, messages must be transmitted to their destination nodes within a certain amount of time; otherwise the messages will be rendered futile. To support real-time multicast communications, computer networks have to guarantee an upper bound on the end-to-end delay from the source node to each of the destination nodes. This is known as the multicast end-to-end delay problem. On the other hand, if the same message fails to arrive at each destination node at the same time, there will probably arise inconsistency or unfairness problem among users. This is related to the multicast delay variation problem. Our research subject is concerned with the minimization of multicast delay variation under the multicast end-to-end delay constraint. The problem has been proved to be NP-complete and a heuristic algorithm for it called DVMA (delay variation multicast algorithm) has been proposed. In this paper we find that in spite of DVMA's smart performance in terms of multicast delay variations, its time complexity is as high as O(klmn/sup 4/). It is strongly believed that such a high time complexity does not fit in a modern high-speed computer network environment. Therefore, we present an alternative heuristic algorithm with a much lower time complexity O(mn/sup 2/) and with a satisfactory performance. Computer simulations also testify that our algorithm is both fast and efficient.
Experimental Evidence for Surface Quenching of the Surface Plasmon on InSb(110) (1984)

In high-resolution electron-energy-loss spectroscopy on clean cleaved InSb(100) surfaces, coupled surface plasmon-phonon losses are studied as a function of primary energy ${E}_{0}$. The ${E}_{0}$ dependence of the relative intensities of the phononlike and plasmonlike losses shows the existence of a dead layer for surface plasmons of free electrons. Comparison of the spacecharge electron density with the bulk concentration indicates that the dead layer arises from a dynamical quenching of the plasmon amplitude rather than from a depletion of carriers due to band bending.
Developmental Vitamin D Deficiency and Risk of Schizophrenia: A 10-Year Update (2010)

There is an urgent need to generate and test candidate risk factors that may explain gradients in the incidence of schizophrenia. Based on clues from epidemiology, we proposed that developmental vitamin D deficiency may contribute to the risk of developing schizophrenia. This hypothesis may explain diverse epidemiological findings including season of birth, the latitude gradients in incidence and prevalence, the increased risk in dark-skinned migrants to certain countries, and the urban-rural gradient. Animal experiments demonstrate that transient prenatal hypovitaminosis D is associated with persisting changes in brain structure and function, including convergent evidence of altered dopaminergic function. A recent case-control study based on neonatal blood samples identified a significant association between neonatal vitamin D status and risk of schizophrenia. This article provides a concise summary of the epidemiological and animal experimental research that has explored this hypothesis.
Glial cell line‐derived neurotrophic factor supports survival of injured midbrain dopaminergic neurons (1995)

Glial cell-lined derived neurotrophic factor (GDNF) has been shown to promote survival of developing mesencephalic dopaminergic neurons in vitro. In order to determine if there is a positive effect of GDNF on injured adult midbrain dopaminergic neurons in situ, we have carried out experiments in which a single dose of GDNF was injected into the substantia nigra following a unilateral lesion of the nigrostriatal system. Rats were unilaterally lesioned by a single stereotaxic injection of 6-hydroxydopamine (6-OHDA; 9 micrograms/4 microliters normal saline with 0.02% ascorbate) into the medial forebrain bundle and tested weekly for apomorphine-induced (0.05 mg/kg s.c.) contralateral rotation behavior. Rats that manifested > 300 turns/hour received a nigral injection of 100 micrograms GDNF, or cytochrome C as a control, 4 weeks following the 6-OHDA lesion. Rotation behavior was quantified weekly for 5 weeks after GDNF. Rats were subsequently anesthetized, transcardially perfused, and processed for tyrosine hydroxylase immunohistochemistry. It was found that 100 micrograms GDNF decreased apomorphine-induced rotational behavior by more than 85%. Immunohistochemical studies revealed that tyrosine hydroxylase immunoreactivity was equally reduced in the striatum ipsilateral to the lesion in both cytochrome C and GDNF-injected animals. In contrast, large increments in tyrosine hydroxylase immunoreactivity were observed in the substantia nigra of animals treated with 100 micrograms of GDNF, with a significant increase in numbers of tyrosine hydroxylase-immunoreactive cell bodies and neurites as well as a small increase in the cell body area of these neurons. The results suggest that GDNF can maintain the dopaminergic neuronal phenotype in a number of nigral neurons following a unilateral nigrostriatal lesion in the rat.
A generalized concept of frequency and some applications (1968)

The system of sine and cosine functions has been distinguished historically in communications. Whenever the term frequency is used, reference is made implicitly to these functions; hence the generally used theory of communication is based on the system of sine and cosine functions. In recent years other complete systems of orthogonal functions have been used for theoretical investigations as well as for equipment design. Analogs to Fourier series, Fourier transform, frequency, power spectra, and amplitude, phase, and frequency modulation exist for many systems of orthogonal functions. This implies that theories of communication can be worked out on the basis of these systems. Most of these theories are of academic interest only. However, for the complete system of the orthogonal Walsh functions, the implementation of circuits by modem semiconductor techniques appears to be competitive in a number of applications with the implementation of circuits for the system of sine and cosine functions.
Glaucoma (1970)

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(<i>R</i>)‐α‐Lipoyl‐Glycyl‐<scp>L</scp>‐Prolyl‐<scp>L</scp>‐Glutamyl Dimethyl Ester Codrug as a Multifunctional Agent with Potential Neuroprotective Activities (2012)

The (R)-α-lipoyl-glycyl-L-prolyl-L-glutamyl dimethyl ester codrug (LA-GPE, 1) was synthesized as a new multifunctional drug candidate with antioxidant and neuroprotective properties for the treatment of neurodegenerative diseases. Physicochemical properties, chemical and enzymatic stabilities were evaluated, along with the capacity of LA-GPE to penetrate the blood-brain barrier (BBB) according to an in vitro parallel artificial membrane permeability assay for the BBB. We also investigated the potential effectiveness of LA-GPE against the cytotoxicity induced by 6-hydroxydopamine (6-OHDA) and H2O2 on the human neuroblastoma cell line SH-SY5Y by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay. Our results show that codrug 1 is stable at both pH 1.3 and 7.4, exhibits good lipophilicity (log P=1.51) and a pH-dependent permeability profile. Furthermore, LA-GPE was demonstrated to be significantly neuroprotective and to act as an antioxidant against H2O2- and 6-OHDA-induced neurotoxicity in SH-SY5Y cells.
Topical cyclosporine administration in rabbits. (1990)

Cyclosporine (CyA) is a potent immunosuppressant, but possesses toxicities which prohibit its unrestricted dosing in patients. The topical administration of CyA could serve to localize the immunosuppressive effect, or could serve as an administration route for patients who cannot tolerate the oral route of administration. We evaluated the potential for transdermal delivery of cyclosporine in rabbits. We sensitized six rabbits to dinitrochlorobenzene (DNCB), treated them topically with either 100 mg CyA or the vehicle, and repeated the DNCB skin testing at 15 and 28 days at the site of administration and at a distal site. In the CyA treated rabbits, significant increases in the suppression of the reaction to DNCB were observed from the control to the 15 day test, and from the 15 to the 28 day testing. Significant differences were also observed between reaction to DNCB at the site of CyA administration and at the distal site. While blood concentrations demonstrated slow and variable absorption of the topically administered CyA, concentrations greater than 1000 ng/ml were frequently observed in blood. We conclude that the local versus a systemic dermatologic effect of CyA can be achieved, and that high blood concentrations are present after topical CyA administration in this model.