gebhart/patrepeval huggingface dataset:
Novel frame synchronization of OFDM scheme for high-speed power line communication systems (2008)

Frame synchronization is an critical factor for an effective operation of OFDM(orthogonal frequency division multiplexing) schemes. In this paper, we propose and analyze an efficient frame synchronization method based on m-sequence of OFDM format for high-speed power line communication systems. Repeated m-sequence is superimposed directly to OFDM frames in the time domain. By utilizing the autocorrelation characteristics of m-sequence, efficient frame synchronization can be achieved without imposing additional complexity. And we also consider frequency offset estimation of OFDM schemes. Both theoretical and simulated results are presented to verify the proposed frame synchronization method. The proposed technique can be applied to design of OFDM-based high speed powerline communication systems.
Electromagnetic Fully Flexible Valve Actuator (2006)

<div class="htmlview paragraph">An electromagnetic fully flexible valve actuator (FFVA) for internal combustion engines is described which offers the potential for significant improvements in fuel economy, emissions, and performance, especially at low end torque, in internal combustion engines. The FFVA offers variable lift and timing combined with controllable seating velocity. It operates on a design principle distinct from existing actuators: the electromagnetic actuator exerts appreciable bidirectional force throughout the device stroke mitigating the need for mechanical spring-derived resonance. The FFVA is a direct drive device with a unique magnetic structure that combines high bandwidth and strong forces to meet the engine performance requirements.</div> <div class="htmlview paragraph">This paper presents the innovative electromagnetic design, simulation, and bench testing of the actuator on a single cylinder engine.</div>
Herpes Simplex Virus Vectors Elicit Durable Immune Responses in the Presence of Preexisting Host Immunity (2002)

Herpes simplex virus (HSV) recombinants are being developed as vaccine vectors for the expression of heterologous antigens. There is concern, however, that preexisting HSV immunity may decrease their effectiveness. We have addressed this issue in an animal model. Immunized mice were inoculated with a replication-defective HSV-1 vector that expressed the Escherichia coli beta-galactosidase protein as a model antigen. We assessed vector efficacy by analyzing the immunoglobulin G (IgG) antibody response and cellular proliferative response directed against beta-galactosidase. We report that the ability of the vector to induce antibody or proliferative responses was not diminished by preexisting immunity to HSV. Of further note, the anti-HSV and anti-beta-galactosidase IgG responses following vector administration were extremely durable in both immunized and naive mice. These results indicate that the ability of a replication-defective HSV-derived vaccine vector to elicit long-lived immune responses in mice is not impaired by prior HSV exposure.
Reactivity of Ti(iv) species hosted in TS-1 towards H2O2–H2O solutions investigated by ab initio cluster and periodic approaches combined with experimental XANES and EXAFS data: a review and new highlights (2007)

This work is intended to underline how the most-advanced experimental and theoretical physical chemistry tools must be used synergistically to understand the reactivity of Ti-silicalite-1 (TS-1) in an important number of low-temperature oxidation reactions with aqueous H(2)O(2) as the oxidant. Literature results are carefully reviewed and accompanied with new, unpublished highlights of both experimental and computational origin. The first part of this work is devoted to a discussion of the defective nature of the material and to the synergic role played by Si vacancies and Ti insertion in the framework. A summary of the experimental Ti-K-edge EXAFS and XANES literature concerning the activated material in vacuo conditions is then presented and compared to the corresponding Ti geometries obtained by ab initio calculations. From such a comparison, the excellent agreement between experiment and theory is evident. A very good agreement is also obtained for the interaction with water and ammonia. For both H(2)O and NH(3), the agreement is due to the possibility to perform experiments in which the probe molecule is dosed from the gas phase, thus allowing to reach the 1 : 1 (or 1 : 2) ratio between the adsorbing Ti sites and the adsorbed molecule. Then, interaction with hydrogen peroxide is discussed, underlining the problems faced in reaching a common view between experimental and theoretical results, owing to the difficulties both in performing experiments where anhydrous H(2)O(2) is dosed on TS-1, and in taking into account the role played by the aqueous medium in the reactivity of Ti(iv) centres toward H(2)O(2) using ab initio calculations. Only once such difficulties have been overcome, by increasing the complexities of both experiments and ab initio models, is a joint-view finally obtained. Where needed, comparison with other experimental results (X-ray and neutron diffraction, NMR, IR, Raman, UV-vis and resonant Raman) is made.
Pesticides and impairment of mitochondrial function in relation with the parkinsonian syndrome (2006)

The Parkinsonian syndrome induced by pesticides is associated with the impairment of mitochondrial function. Toxicants that inhibit selectively NADH-dehydrogenase activity, as rotenone or pyridaben, also show a selective inhibition of O2 uptake and respiratory control in rat brain mitochondria in the presence of NAD-dependent substrates. The IC50 of rotenone and pyridaben for complex I inhibition were in the range 1.7-2.2 microM. The determination of NADH-cytochrome c reductase, succinate-cytochrome c reductase and cytochrome oxidase activities in rat brain submitochondrial showed again the selective inhibition of Complex I by rotenone and pyridaben, whereas paraquat produced a non-selective inhibition affecting all the respiratory chain complexes. In rat brain mitochondria, rotenone and pyridaben markedly decreased mtNOS functional activity with NAD-dependent substrates but not when the substrate was succinate. This observation suggest than mtNOS activity is regulated by the activity of complex I. This regulation and the role of mitochondrial NO diffusion as a signal for mitochondrial biogenesis could have a role in the etiopathology of Parkinson's disease.
ESR centers, interface states, and oxide fixed charge in thermally oxidized silicon wafers (1979)

The ESR Pb center has been observed in thermally oxidized single-crystal silicon wafers, and compared with oxide fixed charge Qss and oxidation-induced interface states Nst. The Pb center is found to be located near the interface on (111) wafers. Its g anisotropy is very similar to that of known bulk silicon defects having SiIII bonded to three other Si atoms; the Pb unpaired electron orbital, however, is exclusively oriented normal to the (111) surface. The Pb center cannot be identified with any other known defect in Si or SiO2; in particular, it is totally unlike the common E′ center of SiO2. In contrast to Qss, both Pb and Nst were found to be greatly reduced by steam oxidation and hydrogen annealing. Both Pb and Nst may be regenerated by subsequent N2 anneals at 500 °C. In a graded series of samples, Pb and Nst are found to be proportional and nearly equal in concentration. This possible confirmation of SiIII at the interface, and correlation with Nst, support the theoretical indication of an SiIII band-gap energy level. The E′ center is unobservable, and if present, exists only in a concentration well below that of Qss. Thus, in addition to a lack of strong correlation with Pb, Qss is evidently not due to E′ centers in their normal charge state. Overall, ESR is judged to be a useful technique for research on silicon wafer defects.
Influence of test conditions on the accuracy of laser flash measurements (2002)

The laser flash method (Parker et al, 1961 J. Appl. Phys. 32 1679-1684) is a well-known technique for the measurement of thermal diffusivity. The advantages of this non-contact measurement technique are, among others, easy sample preparation, fast measurement times, small sample dimensions, and high accuracy. The energy and shape of the laser pulse used for heating the front face of the sample can have a significant influence on the results. The influence of pulse length can be taken care of by an accurate pulse-length correction (Azumi and Takahaski, 1981 Rev. Sci. Instrum. 52 1411 -1413) based on the real shape of the laser pulse. It is shown here that, after the pulse-length correction, the thermal diffusivity is independent of the length of the employed laser pulse for samples with standard dimensions. On the other hand, the employed laser energy can have an influence on the results in the case of samples with strongly temperature-dependent thermal diffusivity. The influence of the pulse energy on the results for various kinds of carbon samples is investigated and a correction routine for its effect is presented.
Effect of cobalamin derivatives on in vitro enzymic DNA methylation: methylcobalamin can act as a methyl donor (1991)

5-Methylcytosine synthesis in DNA involves the transfer of methyl groups from S-adenosyl-methionine to the 5'-position of cytosine through the action of DNA (cytosine-5)-methyltransferase. The rate of this reaction has been found to be enhanced by cobalt ions. We therefore analyzed the influence of vitamin B12 and related compounds containing cobalt on DNA methylation. Vitamin B12, methylcobalamin, and coenzyme B12 were found to enhance significantly the de novo DNA methylation in the presence of S-adenosylmethionine for concentrations up to 1 microM, but at higher concentrations these compounds were found to inhibit DNA methylation. Methylcobalamin behaves as a competitive inhibitor of the enzymatic methylation reaction (Ki = 15 microM), the Km for S-adenosylmethionine being 8 microM. In addition, the use of radioactive methylcobalamin shows that it can be used as a methyl donor in the de novo and maintenance DNA methylation reactions. Thus, two DNA methylation pathways could exist: one involving methylation from S-adenosylmethionine and a second one involving methylation from methylcobalamin.
Demonstration Of Rabi-Flops With Ytterbium 171 Trapped-Ion Qubits (2021)

This paper presents a proof-of-concept for manipulation of Ytterbium 171 trapped-ion qubits through the Rabiflops experiment. This serves as a partial report on an ongoing project aimed at developing a fully operational ion trapping and quantum feedback control laboratory at Stellenbosch University. Despite the bad vacuum conditions during the Rabi-flops experiment, we were able to manipulate the trapped Ytterbium 171 ion qubits with microwave pulses to give out a clear indication of Rabi oscillations. A high rate of ion loss led to the Rabi oscillations profile showing a decay feature within it. This decay feature was modeled and characterized, hence showing that we were losing ions at the rate defined by a time constant of = 4500 -1 seconds.
Effects of Polysaccharide Fucoidin on Cerebrospinal Fluid Interleukin-1 and Tumor Necrosis Factor Alpha in Pneumococcal Meningitis in the Rabbit (1999)

The inflammatory response in bacterial meningitis is mediated by cytokines, such as tumor necrosis factor alpha (TNF-alpha) and interleukin-1 (IL-1), which are produced in the subarachnoid space by different cells, e.g., leukocytes, astrocytes, and microglia. The recruitment of leukocytes into the cerebrospinal fluid (CSF) has been shown to contribute to the neurological damage in this disease, a process which could be enhanced by treatment with antibiotics. In this study, we have used a rabbit meningitis model for two sets of experiments with intracisternal (i.c.) injections of Streptococcus pneumoniae. First, pneumococcal cell wall (PCW) components were injected i.c., inducing an inflammatory response with pleocytosis and increased levels of CSF TNF-alpha) and IL-1 at 6 and 12 h after PCW injection. Treatment with fucoidin, known to inhibit leukocyte rolling, abolished pleocytosis and inhibited the release of TNF-alpha and IL-1. In the second experiment, live pneumococcal bacteria were injected i.c. and treatment with one dose of ampicillin (40 mg/kg of body weight intravenously) was given 16 h after induction of meningitis, causing a sevenfold increase in CSF leukocytes over a 4-h period. CSF IL-1 levels at 16 h were high but did not increase further at 20 h. Also, CSF TNF-alpha levels were high at 16 h and tended to increase at 20 h. Fucoidin treatment prevented the antibiotic-induced increase of CSF leukocytes but had no effect on the TNF-alpha and IL-1 levels. Taken together, fucoidin reduced CSF TNF-alpha and IL-1 levels in acute bacterial meningitis induced by PCW fragments but had no effect later in the course of the disease, when live bacteria were used and an inflammatory increase was caused by a dose of antibiotics.
Advanced Screen Printing "Practical Approaches for Printable &#x00026; Flexible Electronics" (2008)

Screen-printing is not a new technology in the printed circuit industry. However, the combinations of new paste materials and an advanced screen-printing process further increases the value of printable flexible electronics that cannot be made by the traditional photolithography process with copper foils. Additionally, more functionality from the circuits will be generated with new materials in the future. The paper shows an example of electronic sensor module made by multiple screen-printing processes with different ink pastes. All passive components of the circuit were formed by the screen-printing process. The new silver paste makes soldering possible directly with the conductor; therefore the active components are assembled by a standard soldering process that is not available for the traditional polymer thick film circuits.
Evaluation and applications of optical cell density probes in mammalian cell bioreactors (1995)

On-line optical cell density probes were implemented to continuously monitor the cell densities in mammalian cell bioreactor and to achieve advanced bioreactor controls. We tested cell density probes from six manufacturers in high cell density bioreactors. When externally calibrated, Aquasant and Ingold backscattering probes produced the most linear probe responses (PR) versus cell density (CD), followed by the ASR and Cerex laser probes. Monitek and Wedgewood transmission probes had lower resolutions. All probes were tested in two murine hybridoma fermentations. Cell densities varied between 1 x 10(6) cells/mL to 20 x 10(6) cells/mL and the bioreactors were operated for 5 to 7 weeks. For our bioreactors, Aquasant, Ingold, ASR, Wedgewood, and Monitek probes gave satisfactory responses. Little fouling was observed with any probe at the end of 2 weeks. Fouling was a possibility after 3 weeks in one bioreactor but its effect can be easily corrected. Cell density control and specific perfusion control of bioreactors based on the Aquasant probe were achieved. Implementation of cell density probe based perfusion control, instead of "step perfusion adjustments" based on manual hemacytometer control, will result in smoother operation, healthier cultures, increased medium delivery efficiency, and reduced operational excursions.
The Effect of Adding Hexafluoroacetylacetone on Chemical Vapor Deposition of Copper Using Cu(I) and Cu(II) Precursor Systems (1995)

The effect of adding hexafluoroacetylacetone [H(hfac)] on the characteristics of copper chemical vapor deposition (CVD) with beta‐ketonate precursors was studied. A significant difference in this effect is found for a CVD system using Cu(II) and Cu(I) precursors. In the reaction system using copper(II) bis‐hexafluoroacetylacetonate as the Cu(II) precursor, H(hfac) addition improves deposition selectivity on substrate surfaces by eliminating copper nuclei growth on the insulator. In the system using copper(I)‐hexafluoroacetylacetonate trimethylvinylsilane [Cu(hfac)(tmvs)] as, a Cu(I) precursor, selectivity is lost by H(hfac) addition but void formation in blanket CVD films in subquarter micron trenches has been suppressed. These results can be explained by the role of the H(hfac) species in the two deposition reactions. In the Cu(II) precursor system, H(hfac) poisons hydrogen‐induced active surface sites on an insulator. In the Cu(I) system, it acts as a catalytic reagent for the disproportional reaction of Cu(hfac) and enhances nucleation at the first stage of the deposition reaction.
Opioid and opioid-like drug effects on whole-gut transit measured by scintigraphy. (1996)

Tramadol and APAP/C had no effect on gastric emptying or small bowel transit. At equianalgesic doses, tramadol caused less delay in colonic transit than APAP/C for 48 hr and delay in the GC agreed with the subjective complaints of constipation on both drugs.
Interpretation of resonance frequencies recorded during hydraulic fracturing treatments (2014)

Hydraulic fracturing treatments are often monitored by strings of geophones deployed in boreholes. Instead of picking discrete events only, we here use time-frequency representations of continuous recordings to identify resonances in two case studies. This paper outlines an interpretational procedure to identify their cause using a subdivision into source, path, and receiver-side effects. For the first case study, two main resonances are observed both at depth by the downhole geophones and on the surface by two broadband arrays. The two acquisition networks have different receiver and path effects, yet recorded the same resonances; these resonances are therefore likely generated by source effects. The amplitude pattern at the surface arrays indicates that these resonances are probably due to pumping operations. In the second case study, selective resonances are detected by the downhole geophones. Resonances coming from receiver effects are either lower or higher frequency, and wave propagation modeling shows that path effects are not significant. We identify two possible causes within the source area, namely, eigenvibrations of fractures or non-Darcian flow within the hydraulic fractures. In the first situation, 15–10 m long fluid-filled cracks could generate the observed resonances. An interconnected fracture network would then be required, corresponding to mesoscale deformation of the reservoir. Alternatively, systematic patterns in non-Darcian fluid flow within the hydraulic fracture could also be their leading cause. Resonances can be used to gain a better understanding of reservoir deformations or dynamic fluid flow perturbations during fluid injection into hydrocarbon and geothermal reservoirs, CO2 sequestration, or volcanic eruptions.
Predicting Co-Changed Software Entities in the Context of Software Evolution (2009)

Tracing software entity dependencies is a difficult and time-consuming task, and the incomplete changes on software systems are prone to induce bugs. Mining frequent itemset is widely used to find co-changed entities, with which incomplete changes can be detected. In this paper, we present an improved method to predict co-changed software entities in the context of software evolution. In order to extract software entity change transactions precisely, a customized extraction algorithm for change transaction and a fuzzy software entity matching strategy are proposed in our approach, and then Apriori algorithm is reduced to mining the frequent change patterns of software entities efficiently. Experimental results show that our approach can increase the precision by 6%~16%, while the recall reaches 64%.
Perfect Space–Time Block Codes (2006)

In this paper, we introduce the notion of perfect space-time block codes (STBCs). These codes have full-rate, full-diversity, nonvanishing constant minimum determinant for increasing spectral efficiency, uniform average transmitted energy per antenna and good shaping. We present algebraic constructions of perfect STBCs for 2, 3, 4, and 6 antennas
Analyte Flux at a Biomaterial-Tissue Interface over Time: Implications for Sensors for Type 1 and 2 Diabetes Mellitus (2010)

Monitoring metabolic changes at a material-tissue interface combined with biopsy histology helped to formulate an understanding of physiological changes adjacent to implanted glucose sensors. Microdialysate glucose trends were similar over 1-week in T1DM and T2DM; however, differences in other analytes indicated wound healing and metabolic activities in the two patient groups differ. We propose explanations for the specific observed differences based on differential insulin insufficiency/resistance and mitochondrial dysfunction in T1DM versus T2DM.
Enabling Early Audio Event Detection with Neural Networks (2018)

This paper presents a methodology for early detection of audio events from audio streams. Early detection is the ability to infer an ongoing event during its initial stage. The proposed system consists of a novel inference step coupled with dual parallel tailored-loss deep neural networks (DNNs). The DNNs share a similar architecture except for their loss functions, i.e. weighted loss and multitask loss, which are designed to efficiently cope with issues common to audio event detection. The inference step is newly introduced to make use of the network outputs for recognizing ongoing events. The monotonicity of the detection function is required for reliable early detection, and will also be proved. Experiments on the ITC-Irst database show that the proposed system achieves state-of-the-art detection performance. Furthermore, even partial events are sufficient to achieve good performance similar to that obtained when an entire event is observed, enabling early event detection.
A Visualization Tool for Managing and Studying Online Communications (2006)

Most colleges and universities have adopted course management systems (e.g., Blackboard, WebCT). Worldwide faculty and students use them for class communications and discussions. The discussion tools provided by course management systems, while powerful, often do not offer adequate capabilities to appraise communication patterns, online behaviors, group processes, or critical thinking. This paper discusses a Web-based program that represents temporal data as maps to illustrate behaviors of online discussants. Depicting discussions in this manner may help instructors and researchers study, moderate, and/or facilitate group discussions. The paper presents the rationale for program’s development and provides a review of its technical specifications.
Synthesis of peptides, glyco derivatives and glycopeptides from bacterial cell walls (1980)

Syntheisi in solution and in solid phase was used to prepare alanyl-D-isoglutamine ( VI ), alanyl-D-isoglutaminyl-N ε - p -toluenesulfonyl-lysyl-D-alanine ester ( XIII ), alanyl-D-isoglutaminyl-N ε -acetyl-lysyl-D-alanine methyl ester ( XIV ), alanyl-D-isoglutaminyl-N ε -acetyl-lysyl-D-alanyl-pentaglycine methyl ester and amide ( XXXI, XXXII ), alanyl-D-isoglutaminyl-N ε -acetyl-lysyl-D-alanyl-pentaglycyl------------- alanyl-D-isoglutaminyl-lysyl-D-alanine methl ester ( XXXV ), alanyl-D-isoglutaminyl-N ε -acetyl-lysyl-D-alanyl-pentaalanyl-----------------alanyl-D-isoglutaminyl-lysyl-D-alanine methyl ester ( XXXVII ), N-acetylmuramyl-alanyl-D-isoglutaminyl-N ε -acetyl-lysyl-D-alanyl-pentaglycine amide ( XXXIX ), N-acetylmuramyl-alanyl-E-isoglutaminyl-N ε -acetyl-lysyl-D-alanyl-pentaglycyl------------------------ alanyl-D-isoglutaminyl-lysyl-D-alanine methyl ester ( XLI ), and N-acetylmuramyl-alanyl-D-isoglutaminyl-N ε -acetyl-lysyl-pentaalanyl-----------------------------N-acetylmuramyl-alanyl-D-isoglutaminyl-lysyl-D-alanine methyl ester ( XLIII ). The tetrapeptides, nanopeptides, and tridecapeptides show a pronounced pyrogenic effect. Immunoadjuvant activity was observed not only with the glycopeptides but also with nonapeptide XXXI .