gebhart/patrepeval huggingface dataset:
Migration velocity analysis and prestack migration of common-transmitter GPR data (2005)

The accuracy of a migration image of ground-penetrating radar (GPR) depends strongly on the accuracy of permittivity distribution determined from multioffset data. This paper proposes a migration velocity analysis method using a genetic algorithm (GA). The objective function is defined as the summation of normalized zero-delay cross correlation of all common-image point gathers. Under the assumptions that the media are blockwise and that the permittivity of each block can be expressed as a polynomial with limited terms, all coefficients of the permittivity function of each block, which maximize the objective function, are determined by migration velocity analysis method with GA. Prestack migration is performed by a reverse-time migration method based on Maxwell's equations solved by the finite-difference time-domain method with a perfectly matched layer absorbing boundary conditions. The migration velocity analysis method is applied to synthetic common-transmitter datasets to test the method. Then, the velocity analysis and prestack migration method are applied to field data. From the distribution of dielectric constant obtained from the field data, water content is derived, and the depth of a water aquifer is deduced from the water content distribution and a migration stack profile.
Specific Impairment of Human Platelet P2Y <sub>AC</sub> ADP Receptor–Mediated Signaling by the Antiplatelet Drug Clopidogrel (1999)

Clopidogrel is an effective new antiplatelet agent useful for the treatment of ischemic cerebrovascular, cardiac, and peripheral arterial disease. However, the mechanism of clopidogrel action is not well understood, although it is known to inhibit ADP-evoked platelet aggregation. In the current study, the effect of clopidogrel on recently identified human platelet ADP receptors and their signaling pathways was investigated by using platelets from clopidogrel-treated subjects, 6 healthy volunteers (2 females and 4 males) who received 75 mg of clopidogrel daily for 7 days. Blood was taken and various platelet receptor signaling pathways were analyzed before treatment, after 7 days of medication, and 4 weeks after treatment had ceased. Platelet tests included the analysis of aggregation, rapid calcium influx, calcium mobilization from intracellular stores, adenylyl cyclase, and phosphorylation of vasodilator-stimulated phosphoprotein (VASP). The data indicate that clopidogrel does not affect those platelet ADP receptors coupled to cation influx (P2X1 ADP receptors) or calcium mobilization (P2Y1 ADP receptors). In contrast, clopidogrel treatment specifically impairs the ADP receptor coupled to G(i)/adenylyl cyclase (P2Y(AC) ADP receptors). Clopidogrel abolishes the inhibitory P2Y(AC) receptor-mediated ADP effects on prostaglandin E(1)-stimulated, cAMP-dependent phosphorylation of VASP without affecting epinephrine, thrombin, and thromboxane signaling. VASP phosphorylation is known to be closely correlated with the inhibition of platelet and fibrinogen receptor (glycoprotein IIb/IIIa) activation. Therefore, inhibition of the platelet P2Y(AC) ADP receptor and its intracellular signaling, including decreased VASP phosphorylation, is suggested as a molecular mechanism of clopidogrel action.
Effects of nickel sulfate on growth and differentiation of normal human bronchial epithelial cells (1984)

Epidemiological studies have shown that inhalation of nickel compounds enhances the risk of human respiratory cancer. Cultures of normal human bronchial epithelial cells were continuously exposed to a dose (5-20 micrograms/ml) of NiSO4 that reduced their colony forming efficiency by 30-80%. After 40 days of incubation, the cultures consisted of large, squamous cells; mitotic cells were not observed. The cells were then maintained in medium without NiSO4. After 40-75 total days of incubation, colonies of mitotic cells appeared at a rate of 1 colony per 100 000 cells originally at risk; no colonies appeared in control cultures or in cultures exposed to less than 5 micrograms NiSO4/ml for 90 days. Twelve NiSO4-altered cell cultures isolated from five experiments have been expanded into mass cultures. Most of the cell lines have an increased population doubling potential (greater than 50 divisions). Some exhibit aberrations in the squamous (terminal) differentiation process whereas others have lost the requirement for epidermal growth factor for clonal growth. Aneuploidy and marker chromosomes have also been noted. However, none of these NiSO4-altered cell cultures are anchorage independent nor do they produce tumors upon injection into athymic nude mice.
Inter- and intraspecies identification of Bartonella (Rochalimaea) species (1995)

Species of the genus Rochalimaea, recently renamed Bartonella, are of a growing medical interest. Bartonella quintana was reported as the cause of trench fever, endocarditis, and bacillary angiomatosis. B. henselae has been implicated in symptoms and infections of human immunodeficiency virus-infected patients, such as fever, endocarditis, and bacillary angiomatosis, and is involved in the etiology of cat scratch disease. Such a wide spectrum of infections makes it necessary to obtain an intraspecies identification tool in order to perform epidemiological studies. B. vinsonii, B. elizabethae, seven isolates of B. quintana, and four isolates of B. henselae were studied by pulsed-field gel electrophoresis (PFGE) after restriction with the infrequently cutting endonucleases NotI, EagI, and SmaI. Specific profiles were obtained for each of the four Bartonella species. Comparison of genomic fingerprints of isolates of the same species showed polymorphism in DNA restriction patterns, and a specific profile was obtained for each isolate. A phylogenetic analysis of the B. quintana isolates was obtained by using the Dice coefficient, UPGMA (unweighted pair-group method of arithmetic averages), and Package Philip programming. Amplification by PCR and subsequent sequencing using an automated laser fluorescent DNA sequencer (Pharmacia) was performed on the intergenic spacer region (ITS) between the 16 and 23S rRNA genes. It was found that each B. henselae isolate had a specific sequence, while the B. quintana isolates fell into only two groups. When endonuclease restriction analysis of the ITS PCR product was done, three enzymes, TaqI, HindIII, and HaeIII, allowed species identification of Bartonella spp. Restriction fragment length polymorphism after PCR amplification of the 16S-23S rRNA gene ITS may be useful for rapid species identification, and PFGE could be an efficient method for isolate identification.
Influence of channel estimation on the performance of a coherent DS-CDMA system (1997)

Direct-sequence code division multiple access (DS-CDMA) has become one of the favourite candidates for future mobile radio communication systems. The uplink of a coherent DS-CDMA system is investigated. The channel estimation is carried out via a control channel, which is transmitted simultaneously to the data channel. This concept is very closely related to the CODIT-CDMA concept. In the channel estimation, an averaging process is involved, which for long averaging periods, suppresses the noise influence efficiently. On the other hand, long averaging intervals lead to systematic errors in the estimated channel coefficients due to the time-variant behavior of the channel. Taking into account these effects, a closed-form analysis of the data-channel symbol-error rate (SER) is presented. This analysis allows the prediction of the system's performance and helps to optimize the parameter settings for channel estimation.
Process management issues in message-based multiprocessors (2003)

Relatively large message-based multiprocessors can be built but their effective use is limited by inadequate software support and understanding of such systems. An important area that must be addressed is process management. A general message-based multiprocessor system should support dynamic process criterion. This requires algorithms that can decide where to place processes quickly, using small amounts of information, and work concurrently with the application processes. This problem raises a number of issues, including the type of scheduling algorithm that should be used, the information that should be used in the decision-making process, and the communication required between the application processes and the operating system to effectively schedule processes.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
CRISPR-powered electrochemical microfluidic multiplexed biosensor for target amplification-free miRNA diagnostics (2021)

Recently the use of microRNAs (miRNAs) as biomarkers for a multitude of diseases has gained substantial significance for clinical as well as point-of-care diagnostics. Amongst other challenges, however, it holds the central requirement that the concentration of a given miRNA must be evaluated within the context of other factors in order to unambiguously diagnose one specific disease. In terms of the development of diagnostic methods and devices, this implies an inevitable demand for multiplexing in order to be able to gauge the abundance of several components of interest in a patient's sample in parallel. In this study, we design and implement different multiplexed versions of our electrochemical microfluidic biosensor by dividing its channel into subsections, creating four novel chip designs for the amplification-free and simultaneous quantification of up to eight miRNAs on the CRISPR-Biosensor X ('X' highlighting the multiplexing aspect of the device). We then use a one-step model assay followed by amperometric readout in combination with a 2-min-stop-flow-protocol to explore the fluidic and mechanical characteristics and limitations of the different versions of the device. The sensor showing the best performance, is subsequently used for the Cas13a-powered proof-of-concept measurement of two miRNAs (miRNA-19b and miRNA-20a) from the miRNA-17-92 cluster, which is dysregulated in the blood of pediatric medulloblastoma patients. Quantification of the latter, alongside simultaneous negative control measurements are accomplished on the same device. We thereby confirm the applicability of our platform to the challenge of amplification-free, parallel detection of multiple nucleic acids.
Trehalose Crystallization During Freeze-Drying: Implications On Lyoprotection (2009)

Lyoprotectants are stabilizers used to prevent denaturation of proteins during freeze-drying and subsequent storage. In order to be effective, lyoprotectants must be retained amorphous. The physical state of the lyoprotectant is usually characterized by powder X-ray diffractometry of the dried cake. While trehalose is widely used as a lyoprotectant, we report its crystallization during freeze-drying and point out why it may not become evident from characterizing the final lyophile. When an aqueous trehalose solution was cooled to −40 °C, ice was the only crystalline phase observed. However, upon annealing at −18 °C, crystallization of trehalose dihydrate was evident. During drying, the dihydrate dehydrated to substantially amorphous anhydrate. Therefore, analyzing the final dried product will not reveal crystallization of the lyoprotectant during freeze-drying. In light of the observed phase separation of trehalose in frozen solutions, its ability to serve as a lyoprotectant warrants further investigation.
Real-time packet switching: a performance analysis (1988)

The authors model the internal structure of a packet-switching node in a real-time system and characterize the tradeoff between throughput, delay, and packet loss as a function of the buffer size, switching speed, etc. They assume a simple shared-single-path switch fabric, though the analysis can be generalized to a wider class of switch fabrics. They show that with a small number of buffers the node will provide a guaranteed delay bound for high-priority traffic, a low average delay for low-priority traffic, no loss of packets at the input and low probability of packet loss at output.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The Haemophilus influenzae adenylate cyclase gene: cloning, sequence, and essential role in competence (1993)

Competence for transformation in Haemophilus influenzae is stimulated by cyclic AMP (cAMP) and requires the cAMP-dependent catabolite regulatory protein CRP. Thus, understanding the control of competence will require understanding how cAMP levels are regulated. As a first step, we have cloned the H. influenzae adenylate cyclase gene (cya) by complementing the Lac- phenotype of delta cya Escherichia coli. Its sequence specifies an 843-amino-acid protein which has significant identity to other known bacterial adenylate cyclases (41 to 43% and 61% identical to the cya genes of enteric bacteria and of Pasteurella multocida, respectively). As seen in other bacterial cya genes, there is evidence for regulation similar to that demonstrated for E. coli: the presence of a strong consensus CRP binding site within the promoter of the gene may provide feedback control of cAMP levels by repressing cya transcription, and translation may be limited by the weak ribosome binding site and by initiation of protein synthesis with GUG rather than AUG or the UUG used in other bacterial cya genes. We confirmed the essential role of cAMP in competence by constructing and characterizing H. influenzae cya mutants. This strain failed to develop competence either spontaneously or after transfer to a competence-inducing medium. However, it became as competent as its wild-type parent in the presence of exogenous cAMP. This result suggests that the failure of exogenously added cAMP to induce optimum competence in wild-type cells is not due to a limitation to the entry of cAMP into the cells. Rather, it strongly favors models in which competence induction requires both an increase in intracellular cAMP and a second as yet unidentified regulatory event. H. influenzae strains mutant in cya or crp were unable to ferment xylose or ribose. This confirms that influenzae, like E. coli, uses cAMP and CRP to regulate nutrient uptake and utilization and lends increasing support to the hypothesis that DNA uptake is mechanism of nutrient acquisition.
Noncollinear second-harmonic generation in periodically poled KTiOPO_4 excited by the Bessel beam (1999)

Frequency doubling in periodically poled KTiOPO(4) excited by the Bessel-like distribution of the fundamental radiation has been investigated. Theoretical analysis and experiments show that the use of noncollinear geometry provides new possibilities for engineering nonlinear interactions in periodically poled crystals. We demonstrate conversion of the ring-shaped fundamental mode to the axial second-harmonic beam with 30% efficiency for 220-muJ Q -switched Nd:YAG pulses.
Condensed-Matter Simulation of a Three-Dimensional Anomaly (1984)

A condensed-matter analog of (2+1)-dimensional electrodynamics is constructed, and the consequences of a recently discovered anomaly in such systems are discussed.Received 4 September 1984DOI:https://doi.org/10.1103/PhysRevLett.53.2449©1984 American Physical Society
Cachectin/tumor necrosis factor decreases human adipose tissue lipoprotein lipase mRNA levels, synthesis, and activity. (1989)

The effects of the cytokine cachectin/tumor necrosis factor (TNF) on human adipose tissue lipoprotein lipase (LPL) were studied. TNF is produced by activated macrophages and is thought to play a role in mediating hypertriglyceridemia and wasting of adipose tissue triglyceride stores (cachexia) that often accompany infection and malignancy. TNF effects were studied in human adipose tissue fragments maintained in organ culture in the presence of insulin and dexamethasone to induce high LPL activity. Addition of TNF to the culture medium for 20 h caused a dose-dependent inhibition of LPL activity to an average of 37% of controls at 50 U/ml TNF. This inhibition of LPL activity was explained by specific decreases in levels of LPL mRNA (to 40% of controls) and rates of LPL synthesis determined by biosynthetic labeling and immunoprecipitation (to 32% of controls). The decline in LPL synthesis was specific, as it occurred despite a small increase in overall protein synthesis in the presence of TNF. Comparable decreases in LPL activity were observed when TNF was added to adipose tissue cultured solely in the presence of insulin. Thus, similar to results in rodent models, TNF is a potent inhibitor of LPL gene expression in human adipose tissue. TNF may therefore play a role in the disorders of triglyceride catabolism and the pathogenesis of cachexia that occur with stimulation of the immune system in humans.
Spermidine Release from Xenopus Oocytes (1996)

The mechanism of spermidine release from Xenopus oocytes was examined by measuring release of radioactive [3H]spermidine under different ionic conditions, and under voltage-clamp. In normal solution (2 mM K+), the efflux rate is less than 1% per hour, and is stimulated approximately 2-fold by inclusion of Ca2+ (1 mm) in the incubation medium. Spermidine efflux is stimulated approximately 10-fold in high [K+] (KD98) solution. In KD98 solution, efflux is strongly inhibited by divalent cations (Ki for Ba2+ block of spermidine efflux is approximately 0.1 mM), but not by tetraethylammonium ions or verapamil. Spermidine efflux rates were not different between control oocytes and those expressing HRK1 inward rectifier K+ (Kir) channels. When the membrane potential was clamped, either by changing external [K+] in oocytes expressing HRK1, or by 2-microelectrode voltage-clamp, spermidine efflux was shown to be strongly dependent on voltage, as expected for a simple electrodiffusive process, where spermidine3+ is the effluxing species. This result argues against spermidine diffusing out as an uncharged species, or in exchange for similarly charged counterions. These results are the first conclusive demonstration of a simple electrodiffusive pathway for spermidine efflux from cells.
New fluorinated polysiloxanes containing an ester function in the spacer. I. Synthesis and characterization (1994)

Abstract Unsaturated perfluoroalkyl esters derived from undecylenic acid: CH 2 CH(CH 2 ) 8 COOCH 2 CH 2 R F (with R F C 6 F 13 , 2a and R F C 8 F 17 , 2b ) and C 8 F 17 (CH 2 ) 10 COOCH 2 CHCH 2 , 2c were prepared with excellent yields. Their hydrosilylation by methylhydrodimethylsiloxane copolymers of various SiH contents gives new fluorinated polysiloxanes which were examined by 1 H‐ and 13 C‐NMR, GPC, differential scanning calorimetry, and optical polarizing microscopy. Polymers derived from compounds 2a and 2b exhibit mesomorphic structures. © 1994 John Wiley & Sons, Inc.
Structural analysis of polyhydroxyurethane obtained by polyaddition of bifunctional five‐membered cyclic carbonate and diamine based on the model reaction (2001)

This article focuses on the structural analysis of polyhydroxyurethane obtained by the reaction of 2,2-bis[p-(1,3-dioxolan-2-one-4-yl-methoxy)phenyl]propane with a diamine based on the model reaction. The compounds obtained in the model reaction could be separated into hydroxyurethanes containing primary and secondary alcohol groups by preparative gel permeation chromatography with a recycling technique to determine the structures by 1H NMR, 13C NMR, distortionless enhancement by polarization transfer (DEPT) and CH correlation spectroscopy to obtain hydroxyurethane carrying the primary alcohol structure moiety dominantly. The ratios were independent of the reaction temperature but somewhat dependent on the solvents and amines. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 851–859, 2001
Dependence of the interlayer exchange coupling on the constitution of the magnetic layers (1996)

We describe the consequences on the interlayer exchange coupling by the addition of a small amount of Ag impurities within the Co layers of high crystalline quality Co/Cu/Co(Ag) and Cu/Ru/Co(Ag) trilayers, while maintaining the integrity of the spacer layers. We discuss the consequent changes in the amplitude, period, and phase of the coupling in terms of the modification of interfacial spin-dependent potentials.
Fault-detection technique in a WDM-PON (2007)

We propose and demonstrate a new in-service fault-localization method for a wavelength division multiplexing passive optical network (WDM-PON). This scheme uses a tunable OTDR realized by a wavelength-locked Fabry-Perot laser diode. We successfully detect the faults both at the feeder fiber and the drop fibers. The resolution and the dynamic range are 100 m and 12 dB, respectively. In addition, the crosstalk induced by the OTDR signal to the transmission data is negligible.
In vivo studies with a dicalcium phosphate dihydrate/MFP system for caries prevention. (1993)

Recent basic studies have shown that increasing supersaturation with respect to dicalcium phosphate dihydrate (DCPD), above and beyond the amount present in saliva, enhanced the efficacy of fluoride in vitro. Since the combination of monofluorophosphate (MFP) with DCPD abrasive is unique for fluoride stability, dentifrices containing the combination were evaluated in a variety of in vivo tests. MFP with silicon dioxide (silica) abrasive at an equivalent fluoride concentration was used for comparison. The influence of slurries of DCPD or silicon dioxide on the intraoral plaque pH was measured following sucrose challenge in humans. The data indicated that DCPD slurries were more effective than silica in preventing plaque pH drop when compared to silica. A toothpaste containing MFP and DCPD was significantly more effective than an MFP/silica toothpaste. A toothpaste containing radiolabeled DCPD was applied topically in rats' teeth during a cariogenic challenge. The results showed that calcium45 was incorporated into the enamel with a concomitant reduction in enamel solubility. In a rat caries study using MFP/DCPD, matching placebo and MFP/silica, MFP/DCPD dentifrice showed a significantly greater reduction in smooth surface caries. Two dentifrices were also tested in an in situ human model for fluoride uptake in artificial root caries lesions where MFP/DCPD provided a significantly higher fluoride uptake than MFP/silica. A second in situ study in humans evaluated the same dentifrices. MFP/DCPD increased salivary plaque calcium and fluoride. These results of laboratory, animal and in situ studies taken together indicate that the MFP/DCPD combination is unique in providing extra supersaturation in saliva and plaque with concomitant enhanced anticaries efficacy.