gebhart/patrepeval huggingface dataset:
Performance of an OFDM-SDMA based system in a time-varying multi-path channel (2002)

Significant investigation has been conducted towards combining OFDM which mitigates intersymbol interference and SDMA which improves the bandwidth efficiency. OFDM-SDMA systems need accurate channel estimation, because it is from this information that the separation of co-channel users is performed. Usually, the channel is assumed stationary because the frame duration is chosen smaller than the coherence time. However this choice limits the system efficiency. This paper discusses the performance of an OFDM-SDMA based system under a time-varying multi-path channel. The system under study uses the basic combining algorithm based on the linear minimum mean square error (MMSE) criterion for user separation and a pilot based scheme independent from channel statistics for channel estimation. We investigate in particular the effect of the pilot subcarrier arrangement on the BER performance and deduce an optimal configuration in a channel with both delay and Doppler spread.
Escherichia coli heat-labile enterotoxin. Nucleotide sequence of the A subunit gene. (1982)

We report the complete DNA sequence of the Escherichia coli elt A gene, which codes for the A subunit of the heat-labile enterotoxin, LT. The amino acid sequence of the LT A subunit has been deduced from the DNA sequence of elt A. The LT A subunit starts with methionine, ends with leucine, and comprises 254 amino acids. The computed molecular weight of LT A is 29,673. The A subunit of cholera toxin (CT A) has been shown to be structurally and functionally related to the LT A subunit. Comparison of the primary structure of LT A with the known partial amino acid sequence of CT A indicates that the 2 polypeptides share considerable homology throughout their sequences. The NH2-terminal regions exhibit the highest degree of homology (91%), while the COOH-terminal region, containing the sole cystine residue in each toxin is less conserved (approximately 52%). Alignment of homologous residues in the COOH-terminal regions of LT A and CT A indicates that a likely site for proteolytic cleavage of LT A is after Arg residue 188. The resulting A2 polypeptide would be 46 amino acids long, would contain a single cysteine residue, and have Mr = 5261. The elt A nucleotide sequence further predicts that the LT A protein is synthesized in a precursor form, possessing an 18-amino acid signal sequence at its NH2 terminus.
Nitric Oxide-20–Hydroxyeicosatetraenoic Acid Interaction in the Regulation of K<sup>+</sup>Channel Activity and Vascular Tone in Renal Arterioles (1998)

The present study examined whether inhibition of P4504A enzyme activity and the formation of 20-HETE contributes to the activation of K+ channels and vasodilator effects of nitric oxide (NO) in renal arterioles. Addition of an NO donor to the P4504A2 enzyme that produces 20-HETE increased visible light absorbance at 440 nm indicating that NO binds to heme in this enzyme. NO donors also dose-dependently inhibited the formation of 20-HETE in microsomes prepared from renal arterioles. In patch-clamp experiments, NO donors increased the open-state probability of a voltage-sensitive, large-conductance (195+/-9 pS) K+ channel recorded with cell-attached patches on renal arteriolar smooth muscle cells. Blockade of guanylyl cyclase with [1H-[1,2,4]Oxadiazolo[4,3-a] quinoxalin-1-one] (ODQ, 10 micromol/L), or cGMP-dependent kinase with 8R,9S,11S-(-)-9-methoxycarbamyl-8-methyl-2,3,9,10-tetrahydro-8, 11-epoxy-1H,8H,11H-2,7b,11a-trizadibenzo-(a,g)-cy-cloocta-(c ,d, e)-trinden-1-one (KT-5823) (1 micromol/L) did not alter the effects of NO on this channel. In contrast, inhibition of the formation of 20-HETE with 17-octadecynoic acid (1 micromol/L) activated this channel and masked the response to NO. Preventing the NO-induced reduction in intracellular 20-HETE levels also blocked the effects of NO on this channel. Sodium nitroprusside (SNP) increased the diameter of renal interlobular arteries preconstricted with phenylephrine to 80+/-4% of control. Blockade of guanylyl cyclase with ODQ (10 micromol/L) attenuated the response to SNP by 26+/-2%; however, fixing 20-HETE levels at 100 nmol/L reduced the response by 67+/-8%. Blockade of both pathways eliminated the response to SNP. These results indicate that inhibition of the formation of 20-HETE contributes to the activation of K+ channels and the vasodilator effects of NO in the renal microcirculation.
Predicting phonon dispersion relations and lifetimes from the spectral energy density (2010)

We derive and validate a technique for predicting phonon dispersion relations and lifetimes from the atomic velocities in a crystal using the spectral energy density. This procedure, applied here to carbon nanotubes, incorporates the full anharmonicity of the atomic interactions into the lifetime and frequency predictions. It can also account for nonperiodic interactions between phonons and nonbonded molecules near the solid surface. We validate the technique using phonon properties obtained from anharmonic lattice dynamics calculations and thermal conductivities obtained from nonequilibrium molecular-dynamics simulation.
Design and Implementation of Color-Shift Keying for Visible Light Communications (2014)

Color-shift keying (CSK) is a visible light communication intensity modulation scheme, outlined in IEEE 802.15.7, that transmits data imperceptibly through the variation of the color emitted by red, green, and blue light emitting diodes. An advantage of CSK is that the power envelope of the transmitted signal is fixed; therefore, CSK reduces the potential for human health complications related to fluctuations in light intensity. In this work, a rigorous design framework for high order CSK constellations is presented. A key benefit of the frame work is that it optimizes constellations while accounting for crosstalk between the color communication channels. In addition, and unlike previous approaches, the method is capable of optimizing 3-D constellations. Furthermore, a prototype CSK communication system is presented to validate the performance of the optimized constellations, which provide gains of 1-3 dB over standard 805.15.7 constellations.
A model and architecture for pseudo-random generation with applications to /dev/random (2005)

We present a formal model and a simple architecture for robust pseudorandom generation that ensures resilience in the face of an observer with partial knowledge/control of the generator's entropy source. Our model and architecture have the following properties:Resilience. The generator's output looks random to an observer with no knowledge of the internal state. This holds even if that observer has complete control over data that is used to refresh the internal state.Forward security. Past output of the generator looks random to an observer, even if the observer learns the internal state at a later time.Backward security/Break-in recovery. Future output of the generator looks random, even to an observer with knowledge of the current state, provided that the generator is refreshed with data of sufficient entropy.Architectures such as above were suggested before. This work differs from previous attempts in that we present a formal model for robust pseudo-random generation, and provide a formal proof within this model for the security of our architecture. To our knowledge, this is the first attempt at a rigorous model for this problem.Our formal modeling advocates the separation of the entropy extraction phase from the output generation phase. We argue that the former is information-theoretic in nature, and could therefore rely on combinatorial and statistical tools rather than on cryptography. On the other hand, we show that the latter can be implemented using any standard (non-robust) cryptographic PRG.We also discuss the applicability of our architecture for applications such as /dev/(u)random in Linux and pseudorandom generation on smartcards.
An Electrically Tunable Low Frequency Electromagnetic Energy Harvester (2014)

This paper reports the design, fabrication and experimental results of a low frequency electromagnetic energy harvester on FR4. The resonant frequency of the device is tuned electrically by using a generalized load (a capacitance in parallel with a resistance) instead of conventional resistive load. The device produces a maximum load power of 57 μW across 3310 Ω resistive load at 37.5 Hz of untuned resonant frequency under 0.1 g input acceleration. Later, the resonant frequency of the device is experimentally tuned up to 37 Hz successfully by changing the load capacitance from 0 to 10 μF. Though, this tuning comes with reduction in output power. It is observed that only 8.5% of the untuned maximum load power is obtained at the limit of the tuned range.
Subsecond and second changes in inositol polyphosphates in GH4C1 cells induced by thyrotropin-releasing hormone (1987)

It has been demonstrated previously that thyrotropin-releasing hormone (TRH) induces changes in inositol polyphosphates in the GH3 and GH4C1 strains of rat pituitary cells within 2.5-5.0 s. TRH also causes a rapid rise in cytosolic free calcium concentration ([Ca2+]i) in these cells which is due largely to redistribution of cellular calcium stores. Therefore, it has been concluded that TRH acts to release sequestered calcium in these cells via enhanced generation of inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]. If this conclusion were correct, TRH-enhanced accumulation of Ins(1,4,5)P3 should occur at least as rapidly as the increase in [Ca2+]i. We have shown previously that the rise in [Ca2+]i induced by TRH occurs within about 400 ms; thus, it was important to investigate the subsecond time-course of changes in inositol phosphates caused by TRH. Using a rapid mixing device, we have measured changes in inositol polyphosphates on a subsecond time scale in GH4C1 cells prelabelled with myo-[2-3H]inositol. Although TRH did alter inositol polyphosphate metabolism within 500 ms, the changes observed did not reveal a statistically significant increase in Ins(1,4,5)P3 within time intervals of less than 1000 ms. Thus, we have been unable to demonstrate that a TRH-induced rise in Ins(1,4,5)P3 precedes or occurs concomitantly with the rise in [Ca2+]i in GH4C1 cells. Although these results do not disprove the current view that Ins(1,4,5)P3 mediates the action of TRH on intracellular calcium redistribution, we conclude that caution should be exercised in this, and possibly other cell systems, in accepting the dogma that all of the rapid, agonist-induced redistributions of intracellular calcium are mediated by Ins(1,4,5)P3.
Regulation of neuronal differentiation in neuron‐enriched primary cultures from embryonic rat cerebra by platelet activating factor and the structurally related glycerol ether lipid, dodecylglycerol (1991)

Primary cultures enriched in neurons dissociated from embryonic rat cerebra were used to demonstrate that platelet activating factor and the structurally related ether glycerolipid, dodecylglycerol, are readily taken up in small amounts by neurons and that they stimulate the differentiation of neurons. The stimulation of neuronal differentiation was observed as a precocious development of axon-like extensions which correlated with a concentration-dependent increase in neuronal-specific enzyme activities. This stimulation of morphological and neurochemical factors by either platelet activating factor or dodecylglycerol was almost completely abolished by triazolam, a known inhibitor of platelet activating factor function. Neither platelet activating factor nor dodecylglycerol at the concentrations used to achieve stimulation of neuronal differentiation compromised the plasma membrane, as indicated by the lack of leakage of cytoplasmic lactic acid dehydrogenase.
Synthesis and Antimycobacterial Activity of Pyrazine and Quinoxaline Derivatives (2002)

A series of pyrazine and quinoxaline derivatives have been synthesized, and their activity against M. tuberculosis (Mtb) and Mycobacterium avium (MAC) are reported. The 4-acetoxybenzyl ester of pyrazinoic acid and 4'-acetoxybenzyl 2-quinoxalinecarboxylate showed excellent activity against Mtb (MIC ranges of less than 1-6.25 microg/mL) but only modest activity against MAC (MICs of 4-32 microg/mL).
La evolución de las ciberamenazas y sus tendencias (2018)

El pasado mes de mayo el Centro Criptologico Nacional publico la decima edicion del informe anual Ciberamenazas y Tendencias en el cual se exponen, entre otras cuestiones, los principales incidentes ocurridos durante el ano 2017, identifica los actores de estas amenazas, senala cuales han sido los principales metodos de ataque e indica algunas de las posibles tendencias para los proximos meses.
Fibrosis in immune control of mammary‐tumor growth (1992)

In malignancies, an interruption of growth (dormancy) is sometimes observed. In the immunogenic mammary carcinoma MC2, dormancy followed by regression after a period of growth was observed in 18% of s.c. implants in normal mice. Dormant implants removed for histologic examination were invariably found to be completely surrounded by a highly fibrous stroma. Fibrosis was enhanced in immunized mice, and reduced in immuno-deficient mice. Surgical disruption of the fibrous capsule around dormant tumors early (19 +/- 3 days) in the immune response led more frequently to resumed growth, while later (32 +/- 3 days) disruption of the capsule led more frequently to complete regressions. This showed that fibrous capsules that could destroy tumors could also shield them against well-developed systemic immune mechanisms.
Utility-Aware Resource Allocation for Multi-Stream Overlay Multicast (2007)

Overlay multicast, which performs topology construction and data relaying in the application layer, has recently emerged as a promising vehicle for data distribution. In most of the existing systems, only a single stream is assumed for each overlay, and multiple streams, if needed, are distributed separately. In addition, while the overlay node performs relay functions, they generally do not filter the content to match the heterogeneous bandwidth constraints. We consider a more general model, in which a multicast session may consist of multiple data streams, such as video and audio, which are to be delivered to the same set of nodes. The services to these steams are elastic through layer dropping, shaping, or transcoding. In this paper, we focus on an important resource allocation problem in such an adaptive multi-stream multicast framework: Assume that each stream has an associated utility function, how to maximize the total utility of all the streams in a multicast session. The problem involves optimization not only in individual nodes, but also in the global overlay structure. We show that, given a total bandwidth of the streams, there is an efficient and optimal solution for the allocation problem at a single node. The problem however can be much more complicated in a hierarchical structure like tree. Yet we show that, if the utility is concave with bandwidth, i.e., the marginal improvement diminishes with bandwidth increase, then the upstream constraint can be ignored and a local optimal solution is simply the global optimal solution.
Apoptotic Regression of MCF-7 Xenografts in Nude Mice Treated with the Vitamin D<sub>3</sub>Analog, EB1089<sup>1</sup> (1998)

1,25-Dihydroxyvitamin D3 [1,25-(OH)2D3] and its synthetic analog EB1089 induce characteristic morphological features of apoptosis in MCF-7 cells in vitro that coincide with up-regulation of clusterin and cathepsin B, proteins associated with apoptosis in the mammary gland, and with down-regulation of Bcl-2, an antiapoptotic protein. To determine whether vitamin D3 compounds could mediate apoptosis of breast tumors in vivo, we treated nude mice carrying established MCF-7 xenografts with the low calcemic vitamin D3 analog EB1089 via daily injection or sustained release pellets for up to 5 weeks. The volume of tumors from mice treated with 45 pmol/day EB1089 was 4-fold lower than that of tumors from vehicle-treated control mice after 5 weeks. The reduced growth of tumors from EB1089-treated mice was associated with characteristic apoptotic morphology and a marked reduction in the proportion of epithelial cells to stroma. After 5 weeks of treatment with EB1089, MCF-7 tumors exhibited a 6-fold increase in DNA fragmentation (as measured by in situ end labeling) relative to that in control tumors. The enhanced rate of apoptosis in tumors from EB1089-treated mice was coupled to a 2-fold reduction in proliferation (as measured by expression of proliferating cell nuclear antigen) compared with that in tumors from control mice. The antitumor effects of EB1089 were evident at doses that had minimal effects on serum calcium and body weight. EB1089 treatment did not alter the growth of xenografts derived from a vitamin D3-resistant variant of MCF-7 cells (MCF-7(D3Res) cells), which display resistance to EB1089 in vitro, indicating that resistance to EB1089 is maintained in vivo. Tumors derived from both MCF-7 and MCF-7(D3Res) cells underwent apoptotic regression upon estradiol withdrawal, indicating comparable estrogen dependence of tumors with differential sensitivity to vitamin D3 compounds. These are the first studies to demonstrate apoptotic morphology and regression of human breast tumors in response to treatment with a vitamin D3 analog in vivo and support the concept that vitamin D3 compounds can effectively target human breast cancer.
X-ray characterization of a three-element condenser system for soft x-ray projection lithography (1993)

A three-element condenser system has been designed and fabricated for use in a soft x-ray projection lithography facility at Lawrence Livermore National Laboratory. The design uses Kohler illumination to transport x-rays generated by a laser-produced plasma onto an x-ray reflection mask. The condenser optics are coated with molybdenum silicon multilayers to provide peak reflectance at an operating wavelength of approximately 13.0 nm.
A review of: “<i>ENGINEERING ECONOMY</i>” (1960)

(1960). A review of: “ENGINEERING ECONOMY”. The Engineering Economist: Vol. 6, No. 1, pp. 38-39.
A low-cost and very compact wireless terminal integrated on the back of a waveguide planar array for 26 GHz band fixed wireless access (FWA) systems (2005)

A compact wireless terminal (WT) with a high-gain planar array has been developed for the Wireless IP Access System (WIPAS), which is a point-to-multipoint Fixed Wireless Access (FWA) system in the 26 GHz band. For the point-to-multipoint FWA services in rural areas, the drastic cost and size reduction of WT with the high-gain antennas and RF module is indispensable. In this paper, remarkable cost reduction of 1/10 and downsizing of 1/5 are realized by using an alternating phase fed single layer waveguide array antenna and Microwave Monolithic IC (MMIC) technologies. This terminal is 190/spl times/190/spl times/55 mm/sup 3/ in volume and less than 2.0 kg in weight which accommodates over 31 dBi very high efficiency antenna with a radome, RF module, IF modules, application specific IC (ASIC) for modem, time division multiple access (TDMA) equipment control, and medium access control (MAC). Only an Ethernet cable with 24 V dc power supply is attached on the terminal.
Temperature Dependence of the Hardness of Single-phase Cementite Films Prepared by An Electron-Shower PVD Method (2000)

To design advanced steel, it is important that the mechanical properties of the cementite phase are studied. However, few papers on these properties have been published. For those that have been published, the samples were cementite embedded in steels or extracted from steels by electrolysis.The purpose of this paper is to prepare a thick cementite film without the oxide, and to study the temperature dependence of the hardness in detail.A single phase cementite film, 3 μm thick, was prepared by the electron-shower PVD method. The composition of the film was Fe : C : O=76 : 24 : 0. The Vickers hardness of the cementite was 1140 at room temperature and decreased to half at 400°C. The hardness of composite film of Fe and cementite is explained by the law of mixture. The cementite film was oxidized above 400°C in atmosphere, but was very stable at room temperature.
Resiliency Assessment in Distribution Networks Using GIS Based Predictive Risk Analytics (2018)

A new predictive risk-based framework is proposed to increase power distribution network resiliency by improving operator understanding of the energy interruption impacts. This paper expresses the risk assessment as the correlation between likelihood and impact. The likelihood is derived from the combination of Naive Bayes learning and Jenks natural breaks classifier. The analytics included in a GIS platform fuse together a massive amount of data from outage recordings and weather historical databases in just one semantic parameter known as failure probability. The financial impact is determined by a time series-based formulation that supports spatiotemporal data from fault management events and customer interruption cost. Results offer prediction of hourly risk levels and monthly accumulated risk for each feeder section of a distribution network allowing for timely risk mitigation.
A power electronic controlled dump load with negligible harmonics for accurate loading used in testing small wind turbines (2010)

Permanent magnet synchronous generators (PMSG) are at the core of small scale wind power generators manufactured by a wide range of manufacturers in different configurations: vertical or horizontal axis blades, with various geometries and aerodynamics of the blades; by installing these small scale wind turbines in very large numbers at household levels, it is expected that these will make a positive contribution to the increase of renewable energy generation, reducing the use of fossil fuels that are blamed for climate change. However, a proper evaluation of the technical specification of these small scale wind generators in various weather conditions is necessary in order to assess the full potential of benefits. This paper reports on the implementation and testing of a power electronic dump load that allows continuously adjustable loading of a PMSG with sinusoidal currents and have the capability to self synchronize to its frequency/speed whilst avoiding transient/loosing of synchronism.
Spatial Resolution Improvement of Distributed Raman Temperature Measurement System (2013)

Ensuring the synchronization of backscattered Raman light and improving the sampling rate are of great importance to improve the spatial resolution of a distributed Raman temperature measurement system. To keep the synchronization of the Anti-Stokes and Stokes light and improve the sampling rate, four effective methods are proposed in this paper. First, the asynchrony caused by the difference in the hardware is eliminated by attaching a fiber to the pigtail of APD, which detects the earlier arriving signal. Next, the data acquisition card chooses different sampling rates for the Anti-Stokes and Stokes light according to the velocity of propagation. Then, a new algorithm is adopted to decrease the difference in the fiber position between the Anti-Stokes and Stokes signals. Finally, the optical switch with different length of pigtails is applied to improve the sampling rate without upgrading the hardware of data acquisition card. By theoretical analysis and experimental simulation, the proposed measures in this paper can improve the spatial resolution effectively.