gebhart/patrepeval huggingface dataset:
Regulation of HIV-1 expression by cytokine networks in a CD4+ model of chronic infection (1993)

Using the CD4+ model of chronic HIV-1 infection, OM-10.1, we investigated the influence of TNF-alpha regulatory networks on induced viral expression. Previously, OM-10.1 cultures were characterized to respond to exogenous TNF-alpha, as nearly 100% of the cells were activated to express HIV-1 within 24 h. In this study, OM-10.1 cells were pulse-treated, by applying exogenous factors for short periods of time and then washing, to determine if autocrine TNF-alpha could sustain HIV-1 activation in the absence of additional exogenous stimulation. After a TNF-alpha pulse treatment, the progressive increase of HIV-1-expressing OM-10.1 cells was prevented by the continuous presence of anti-TNF-alpha mAb. The inductive activity of supernatant from TNF-alpha pulse-treated OM-10.1 cultures was completely removed by absorption on immobilized anti-TNF-alpha mAb. In addition, TNF-alpha pulse-treated OM-10.1 cells activated HIV-1 expression in untreated OM-10.1 cells when cultured across a permeable membrane indicating paracrine effects. Interestingly, if TNF-alpha pulse-treated OM-10.1 cells were further pulse-treated with anti-TNF-alpha mAb, a marked reduction in autocrine TNF-alpha was observed although the level of newly synthesized TNF-alpha mRNA remained unaffected. A similar degree of inhibition over autocrine TNF-alpha production was observed when soluble TNF receptors were used as the second pulse treatment in these experiments. Although the applicability of these results to in vivo chronically HIV-1-infected cells remains to be realized, these results do indicate that activated HIV-1 expression can be influenced by self-perpetuating mechanisms during periods of limited exogenous stimulation. Furthermore, physiologic mechanisms involving soluble cytokine receptors that counteract autocrine and paracrine activation of HIV-1 expression are shown here to play a regulatory role.
Linking immune-mediated damage to neurodegeneration in multiple sclerosis: could network-based MRI help? (2021)

Inflammatory demyelination characterizes the initial stages of multiple sclerosis, while progressive axonal and neuronal loss are coexisting and significantly contribute to the long-term physical and cognitive impairment. There is an unmet need for a conceptual shift from a dualistic view of multiple sclerosis pathology, involving either inflammatory demyelination or neurodegeneration, to integrative dynamic models of brain reorganization, where, glia-neuron interactions, synaptic alterations and grey matter pathology are longitudinally envisaged at the whole-brain level. Functional and structural MRI can delineate network hallmarks for relapses, remissions or disease progression, which can be linked to the pathophysiology behind inflammatory attacks, repair and neurodegeneration. Here, we aim to unify recent findings of grey matter circuits dynamics in multiple sclerosis within the framework of molecular and pathophysiological hallmarks combined with disease-related network reorganization, while highlighting advances from animal models (<i>in vivo</i> and <i>ex vivo</i>) and human clinical data (imaging and histological). We propose that MRI-based brain networks characterization is essential for better delineating ongoing pathology and elaboration of particular mechanisms that may serve for accurate modelling and prediction of disease courses throughout disease stages.
Levels of 33Cl Via the 32S(d,n)33Cl Reaction (1972)

The 32 S(d,n) 33 Cl reaction has been studied at two bombarding energies of 4.70 and 5.50 MeV. The Q value of this reaction has been measured to be 62 ± 9 keV. The excitation energies of the levels observed are 812 ± 4, 1993 ± 6, 2351 ± 5, 2688 ± 4, and 2851 ± 4 keV. Neutron angular distributions for transitions to these states have been analyzed with DWBA and Hauser–Feshbach theories to yield l p values and spectroscopic factors. The l p values for transitions to the ground, 0.812 and 2.851 MeV states are 2, 0, and 1 respectively, in agreement with previous results. The analysis also favors l p values of 2 and 3 for transitions to the 2.351 and 2.688 MeV states respectively. The results have been compared with several other experimental and theoretical investigations.
Calcium responses elicited by nucleotides in macrophages. Interaction between two receptor subtypes. (1993)

The responses elicited by ATP and UTP in macrophages (measured by microfluorescence and in patch-clamp) present marked differences. The release of Ca2+ from intracellular stores induced by ATP is due to the activation of P2U receptors. These receptors can be activated by ATP4- and by MgATP2-, with apparent K0.5 values of 0.65 and 6.5 microM, respectively. The release of Ca2+ due to activation of P2U receptors by either ATP or UTP is followed by the opening of ionic channels leading to an influx of Ca2+. A second pathway for Ca2+ influx results from the opening of P2Z receptor channels triggered by adenosine-5'-O(1-thiotriphosphate) or ATP but not by UTP. The form of ATP that activates P2Z receptors is ATP4- (with a K0.5 of 0.5 microM). In voltage-clamped cells, the inward current activated by ATP4- is transient, partly because it inactivates and partly because it is rapidly masked by the development of a quinine-sensitive Ca(2+)-dependent K+ current. In current-clamp, macrophages stimulated by UTP remain normally polarized, whereas ATP depolarizes them. This P2Z-mediated depolarization results in an inhibition of the influx of Ca2+, which explains part of the difference between the time courses of the Ca2+ responses elicited by ATP and UTP.
Sex differences of innate immune activation in amyloid positive predementia cases (2020)

Abstract Background Innate immunity is linked to Alzheimer’s disease, as shown by genome‐wide association studies and experimental data. There is, however, a sexual dimorphism in the activation of the innate immune system. Here, we investigate sex‐differences in immune activation by comparing glial activation markers in CSF from males and females with amyloid pathology as compared to healthy controls. Method A total of 110 CSF Aβ‐ healthy controls (n=52 males and n=58 females), and 121 CSF Aβ+ (n=70 males and n=51 females) non‐demented cases with cognitive symptoms from the Dementia Disease Initiation (DDI) cohort were included in the analyses. CSF levels of sTREM2, YKL‐40 and MCP‐1 were determined using Mesoscale Discovery. Amyloid pathology was determined using CSF Aβ1‐42 threshold of 708 pg/mL. CSF total tau was included in our models to investigate potential sex differences of active neurodegeneration. We compared CSF concentrations using three‐way ANCOVA with age as a covariate, investigating main effects, two‐way interaction effects between sex and CSF Aβ status and three‐way APOE‐ε4 interactions with sex and CSF Aβ. Result Significant interaction effects between sex and CSF Aβ status showed lower CSF YKL‐40 (p&lt;.001), sTREM2 (p&lt;.05) and MCP‐1 (p&lt;.0001) levels in Aβ+ women as compared to males. No differences in levels were found between male and female healthy controls. Furthermore, we found that only Aβ+ males had increased YKL‐40 (p&lt;.001), sTREM2 (p&lt;.05) and MCP‐1 (p&lt;.05) levels compared to healthy controls, whilst Aβ+ females showed no significant differences in levels. Men had slightly higher levels of CSF total tau as compared to women, however, this difference did not reach the threshold for statistical significance (p=.07). No main effects or interaction effects with APOE‐ε4 were found. Conclusion We found consistent differences in innate immune activation in Aβ+ females, but not related to APOE‐ ε4 genotype. However, a slight non‐significant increase in a CSF marker of neurodegeneration in men may in part contribute to the observed differences in immune activation in our sample. The low level of innate immune activation has yet to be linked to differences in disease progression.
Timing and Intensity of Tutoring: A Closer Look at the Conditions for Effective Early Literacy Tutoring (2002)

In this article we report data from a longitudinal study of one–to–one tutoring for students at risk for reading disabilities. Participants were at–risk students who received phonics–based tutoring in first grade, students who were tutored in comprehension skills in second grade, and students tutored in both grades 1 and 2. At second–grade posttest, there were significant differences in word identification and word attack between students who were tutored in first grade only compared to students who were also tutored in second grade, favoring students who were tutored in first grade only. Overall, there were no advantages to a second year of tutoring. For students tutored in second grade only, there were no differences at second–grade posttest compared to controls. Schools may have selected students who did not respond to first–grade tutoring for continued tutoring in second grade. Findings are discussed in light of decisions schools make when using tutors to supplement reading instruction for students with reading difficulties.
Reduction of Nitrous Oxide to Dinitrogen by a Mixed Valent Tricopper-Disulfido Cluster (2009)

The greenhouse gas N(2)O is converted to N(2) by a mu-sulfido-tetracopper active site in the enzyme nitrous oxide reductase (N(2)OR) via a process postulated to involve mu-1,3 coordination of N(2)O to two Cu(I) ions. In efforts to develop synthetic models of the site with which to test mechanistic hypotheses, we have prepared a localized mixed valent Cu(II)Cu(I)(2) cluster bridged in a mu-eta(2):eta(1):eta(1) fashion by disulfide, [L(3)Cu(3)(mu(3)-S(2))]X(2) (L = 1,4,7-trimethyl-triazacyclononane, X = O(3)SCF(3)(-) or SbF(6)(-)). This cluster exhibits spectroscopic features superficially similar to those of the active site in N(2)OR and reacts with N(2)O to yield N(2) in a reaction that models the function of the enzyme. Computations implicate a transition state structure that features mu-1,1-bridging of N(2)O via its O-atom to a [L(2)Cu(2)(mu-S(2))](+) fragment and provide chemical precedence for an alternative pathway for N(2)O reduction by N(2)OR.
Enhancing TCP performance in wide-area cellular wireless networks: transport level approaches (2004)

Internet technology-based architectures and protocols for supporting multimedia traffic over wireless networks are evolving. Since TCP (Transmission Control Protocol)/IP (Internet Protocol) is the standard network protocol stack on the Internet, its use over the next-generation wireless mobile networks is a certainty. Performance of TCP would be one of the most critical issues in IP-based data networking over wireless links. This article presents a comprehensive study on the performances of the basic TCP variants (e.g., TCP Tahoe, TCP Reno, TCP New-Reno, SACK TCP, FACK TCP) in wide-area cellular wireless networks. For the basic TCP variants, an in-depth analysis of the transport-level system dynamics is presented based on computer simulations using ns-2. Impacts of variations in wireless channel error characteristics, number of concurrent TCP flows and wireless link bandwidth on the average TCP throughput and fairness performances are investigated. The maximum achievable throughput under window-based end-to-end transmission control is also evaluated and the throughput performances of TCP New-Reno, SACK TCP and FACK TCP are compared against this ideal TCP throughput performance. To this end, an overview of the major modifications to the basic TCP variants based on transport-level approaches to enhance TCP performance in wired-cum-wireless networks is presented.
Michael-Induced Ring Closure to 2-Azidocyclopropane-1,1-dicarboxylates and their Staudinger Reduction to 5-Alkoxy-3-(alkoxycarbonyl)pyrrolidin-2-ones (2006)

An easy and short synthesis of new β-azidocyclo­propanedicarboxylates, a rather unexplored class of conformationally constrained N-protected β-aminocyclopropanecarboxylic acid derivatives, is described. Michael-induced ring closure (MIRC) of sodium azide to 2-bromoalkylidenemalonates in alcoholic solvents leads to 3,3-dialkyl-2-azidocyclopropane-1,1-dicarboxylates, whereas other polar solvents give increasing amounts of competitive 2-azidoalkylidenemalonates. The reactivity of the azidocyclopropanes was investigated under reducing conditions, giving an easy access to diastereomeric mixtures of 5-alkoxy-3-(alkoxy­carbonyl)pyrrolidin-2-ones.
Chemical sensors based on SPR in a Plastic Optical Fiber: Simultaneous detection of Fe(III) and Cu(II) (2014)

In this work we present a multichannel chemical sensor based on Surface Plasmon Resonance (SPR) in a Plastic Optical Fiber (POF), for the detection of metal ions. The SPR sensing platform was realized removing the cladding of a plastic optical fiber along half circumference, spin coating on the exposed core a buffer of Microposit S1813 photoresist, and finally sputtering a thin gold film by using a sputtering machine. The planar gold layer can be employed for the preparation of a Self Assembled Monolayer (SAM) with specific binding receptor. In the present study two different ligands for Fe(III) and Cu(II) are linked on the gold surface obtaining two SAM-POF sensors.
A review of virtual reality and haptics for product assembly: from rigid parts to soft cables (2013)

Purpose The use of virtual reality for product assembly has been studied for more than 20 years; however its practical application in industry is still very much in its infancy. Haptics is a new and important interaction method for virtual reality, and currently constitutes a strong and growing research area; however despite this, its application in industry still remains virtually unknown. This paper seeks to address this issue. Design/methodology/approach This paper presents a comprehensive survey of the topics of virtual reality and haptics for product assembly, from rigid parts to soft cables, and investigates some new ideas and recent advances in the area. The survey work has been divided into two parts: addressing rigid parts and soft cables. The main focus of part two, the present work, concentrates on virtual reality and haptics for soft cable design and assembly. Findings In the first instance, the main research groups and typical systems are investigated, followed by extensive exploration of the major research issues. The latter can be reviewed from three perspectives: geometry modelling, physical modelling and haptics interaction. Finally, the barriers that prevent successful application of virtual assembly are also discussed, and the future research directions are summarized. Originality/value This paper presents a comprehensive survey of the topics of virtual reality and haptics for product assembly, from rigid parts to soft cables, and investigates some new ideas and recent advances in the area.
Lunar seismology: The internal structure of the Moon (1981)

Tables A1–A4 and Figures A1–A3 are available with entire articleon microfiche. Order from American Geophysical Union, 2000 Florida Avenue, N.W., Washington, D.C. 20009. Document J81‐003;$1.00. Payment must accompany order. The arrival times of direct P and S waves, measured on seismograms recorded from natural lunar seismic events, have been analyzed using linearized inversion and parameter search methods to simultaneously determine event locations, origin times, and structural parameters (seismic velocities). Polarization‐filtered record section plots are correlated with theoretical travel time curves to identify later phases and obtain additional structural and velocity information. Shear wave amplitudes plotted as a function of distance provide data on the existence and magnitude of seismic velocity gradients in the interior. These studies are used to delineate the structure of the moon below the crust to a depth of about 1100 km. This structure has been divided into an upper and a lower mantle. The upper mantle, from 60‐ to 400‐km depth, has average seismic wave velocities of V p = 7.70 ±0.15 km/s and V s = 4.45 ± 0.05 km/s with corresponding Q values (taken from the literature) of Q p ∼ 5000 and Q s ∼ 3000. The shear wave velocity decreases with a negative gradient of at most −6 × 10 −4 km/s/km, implying a V s variation of from 4.57 km/s at 60‐km depth to 4.37 km/s at 400‐km depth; this decrease can be accounted for by increasing temperature, and so no major compositional gradient is required in the upper mantle. A small negative P wave velocity gradient may also be present. Between 400‐ and 480‐km depth there is a transition zone with a sharply decreasing shear wave velocity and possibly an accompanying small decrease in V p . The dominant shear velocity decrease may occur at a 480‐km interface and may represent a compositional change, although the effects of increased temperature cannot be totally ruled out. The lower mantle extends from 480‐km depth to at least 1100‐km depth; few seismic waves recorded by the lunar network penetrate below 1100 km. The average velocities are V p = 7.6 ± 0.6 km/s and V s = 4.2 ± 0.1 km/s. Q values (taken from the literature) are Q p ∼ 1500 and Q s ∼ 1000. Below 1100 km there is some indication that the attenuation may increase still further for shear waves, with Q s dropping to a few hundreds or less. This seismic model of the moon is well constrained, with uncertainties on the above values given explicitly by the analysis methods, and so it serves as a strong control on the present‐day lunar compositional and thermal structure.
Experimental demonstration of a mmWave passive access point extender\n based on a binary reconfigurable intelligent surface (2021)

As data rates demands are exploding, 5G will soon rely on mmWaves that offer\nmuch higher bandwidths. Yet at these frequencies, attenuation and diffraction\nof waves require point to point communications with beamforming base stations\nthat are complex and power greedy. Furthermore, since any obstacle at these\nfrequencies completely blocks the waves, the networks must be extremely dense,\nresulting in dramatic increase of its cost. One way to avoid this problem is to\nredirect beams coming from base stations at many locations with Reconfigurable\nIntelligent Surfaces, in order to increase their coverage even in cluttered\nenvironments. Here we describe and experimentally demonstrate a binary tunable\nmetasurface operating at 28~GHz, based on standard PCB and off the shelves PIN\ndiodes. We show that it can be used as a Reconfigurable Intelligent Surface\nthat beamforms an incoming plane wave at a given angle to one or several\noutgoing plane waves at angles reconfigurable in real time. Most importantly we\nuse this 20~cm$\\times$20~cm reconfigurable Intelligent Surface alongside\nsoftware defined radio and up/down converters at 28~GHz, and demonstrate a\nwireless link between an emitter and a receiver 10~meters away, in a non line\nof sight configuration, hence proving the validity of the approach.\n
Cellular Mechanisms of Exogenous Peptide Binding to HLA Class II Molecules in B Cells (1994)

We have investigated the ability of APC Class II molecules to bind and release exogenous peptides, two phenomena that are still poorly understood. In order to investigate the half-life of the complex of an exogenous peptide with DR molecules we have evaluated the uptake and release of the radiolabeled peptide 17-29-Tyr of influenza virus matrix protein (MA 17-29-Y) by a B-EBV cell line at different times and under different conditions. We have found that the kinetics of both binding and release of the peptide are very fast in living cells; using glutaraldehyde-fixed cells, the kinetics of the two phenomena are slow, closely resembling those observed with the same peptide and purified, immobilized DR molecules. As confirmed by the study of a specific T-cell clone activation, the Class II-MA 17-29-Y complexes are short-living ones, with an average half-life of 55 min, and the DR molecules that bind exogenous peptides continuously undergo peptidic exchange. These data, taken together, suggest that the APC are endowed with cellular mechanisms that increase the efficiency of both the loading and the unloading of Class II HLA with exogenous peptides. These mechanisms do not appear to require ATP or to involve newly synthesized Class II molecules, intracellular acidic compartments, or the microtubule-microfilament system. On the other hand, an undamaged cell membrane appears to be crucial for an efficient binding.
Nonclassical Potentiometric Indicator Electrodes with Dual Sensitivity (1999)

Classically all titrations are divided into four groups: acid-base, redox, precipitation and complexometric. Correspondingly, four kinds of potentiometric indicator electrodes can be distinguished: pH, redox, anionic and cationic. By deliberate exploitation of the mixed conductivity of conducting polymers, a new class of indicator electrodes has been designed. With these electrodes, unique potentiometric titrations can be performed with titration jumps that originate from a change in redox potential and a change in ion activity and monitored by the same indicator electrode in the course of titration. The mechanism of the indicator electrode with dual sensitivity is discussed, the theoretical implications of the application of such electrodes in stepwise titrations are outlined, and model experimental titrations, including an unusual redox-precipitation titration, are presented.
Fault diagnosis, failure prognosis and fault tolerant control of aerospace/unmanned aerial systems (2016)

Fault-tolerant control and operation of complex unmanned and aircraft systems is an emerging technology intended to provide the designer and operator with flexibility, interoperability, sustainment and reliability under changing operational requirements or mission profiles. Moreover, it is intended to reconfigure online hardware and software to maintain the operational integrity of the system in the event of contingencies (fault/failure modes). This paper presents an hierarchical architecture that uses available sensor information, fault isolation, failure prognosis, system restructuring and controller reconfiguration. The fault tolerant control framework relies on prognostic information to reconfigure system components and preserve the operational integrity of the aircraft. The hierarchical structure starts at the lowest component level and migrates to the middle system/subsystem level ending with the final mission level. We illustrate the methodology using an electro-mechanical actuator (EMA).
300 GHz-band 50 Gbit/s dual channel link using industrial silicon photonics technology (2019)

We demonstrate the use of an industrial silicon photonics photodiode towards indoor THz links in the 300 GHz band. The devices are presented and two links are reported: the first one in a single channel operation QPSK-25 Gbit/s signaling and the second one using a dual channel configuration, 260 and 280 GHz, reaching 50 Gbit/s. In each case, the detection is done using a III-V GaAs Schottky-based sub-harmonic mixer.
Mid-IR Kerr-Lens Mode-Locked Polycrystalline Cr2+:ZnS Laser with 0.5 MW Peak Power (2015)

We report femtosecond polycrystalline Cr2+:ZnS laser at 2.4 µm central wavelength with 41 fs pulse duration, 1.9 W average power and 79 MHz pulse repetition rate that corresponds to 0.5 MW peak optical power.