gebhart/patrepeval huggingface dataset:
High frequency signal integrity in high-density assemblies (2008)

The demand for faster, portable and reliable electronic devices is increasing the pressure on the development of assembly techniques for signal integrity (SI). The advance of integrated circuits toward a large number of Input/Output (I/Os), a high number of operations and up to microwave communication frequencies, is behind the drive for the search for new packaging solutions. The materials and assembly techniques have an important impact on the propagation of high speed signals. Signal integrity issues emerge due to the electrical losses of materials, reflections from impedance discontinuities in the signal path and fast transitions of the signals. For these reasons, signal integrity in lead-free connections of WLCSP, flip chip (FC) and Integrated Module Board (IMB) assemblies were investigated up to 50 GHz. \n The increase of conductor loss resulting from the presence of thick oxide layers on the surface of solder bumps of hot running components was experimentally studied for the first time. Utilizing theoretical calculations, a design rule was developed to account for the 40 % increase in losses due to the presence of oxide layers at high frequencies. The research into the influence of solder microstructure on signal quality showed that it did not negatively affect the wave propagation. Experimental results proved that the presence of underfills and high density routing on printed wiring boards (PWBs) under the WLCSP components, detuned the components and the connections. The effects of three different underfills on signal propagation were studied. It was proven that the changes resulting from the rheology and parameters of curing process influence the losses and reflections of circuits. \n The analysis of microwave performances of flip chip (FC) and Integrated Module Board (IMB) assembly techniques demonstrated that they are well suited to Radio frequency (RF) and high speed applications. Comparison showed that IMB performed better as the wave encountered smaller discontinuities and had an optimized propagation path. Full wave simulations of IMB assemblies were performed considering finite ground coplanar waveguide (FGCPW), microstrip and stripline connections with stack-ups that included high dielectric constant materials and four connection possibilities. The research was carried out in the domains of both frequency and time to rigorously determine the sources of signal reflections. The results emphasized that in the design for match impedance and optimal current return path, discontinuities and reference planes had significant impact on signal integrity.
Phytase improves iron bioavailability for hemoglobin synthesis in young pigs. (1999)

Dietary phytase supplementation improves bioavailabilities of phytate-bound minerals such as P, Ca, and Zn to pigs, but its effect on Fe utilization is not clear. The efficacy of phytase in releasing phytate-bound Fe and P from soybean meal in vitro and in improving dietary Fe bioavailability for hemoglobin repletion in young, anemic pigs was examined. In Exp. 1, soybean meal was incubated at 37 degrees C for 4 h with either 0, 400, 800, or 1,200 units (U) of phytase/kg, and the released Fe and P concentrations were determined. In Exp. 2, 12 anemic, 21-d-old pigs were fed either a strict vegetarian, high-phytate (1.34%) basal diet alone, or the diet supplemented with 50 mg Fe/kg diet (ferrous sulfate) or phytase at 1,200 U/kg diet (Natuphos, BASF, Mt. Olive, NJ) for 4 wk. In Exp. 3, 20 anemic, 28-d-old pigs were fed either a basal diet with a moderately high phytate concentration (1.18%) and some animal protein or the diet supplemented with 70 mg Fe/kg diet, or with one of two types of phytase (Natuphos or a new phytase developed in our laboratory, 1,200 U/kg diet) for 5 wk. In Exp. 2 and 3, diets supplemented with phytase contained no inorganic P. In Exp. 1, free P concentrations in the supernatant increased in a phytase dose-dependent fashion (P<.05), whereas free Fe concentrations only increased at the dose of 1,200 U/kg (P<.10). In Exp. 2 and 3, dietary phytase increased hemoglobin concentrations and packed cell volumes over the unsupplemented group; these two measures, including growth performance, were not significantly different than those obtained with dietary supplemental Fe. In conclusion, both sources of phytase effectively degraded phytate in corn-soy diets and subsequently released phytate-bound Fe from the diets for hemoglobin repletion in young, anemic pigs.
A multiple beam management scheme on 5G mobile communication systems for supporting high mobility (2016)

Due to the consistently increasing data traffic, current fourth generation (4G) mobile communication systems have been rapidly congested. To accommodate the emerging data traffic, the fifth generation (5G) mobile communication systems have been developed based on the introduction of millimeter-wave bands and adoption of beamforming and massive antenna structure. However, due to the structural features of the 5G mobile communication systems operating a lot of narrow beams, it is difficult for high-speed mobile users to provide stable service environments. Therefore, In this paper, we propose a novel handover and radio resource management concept for overcoming the limitations. Our simulation results indicate that the proposed scheme can improve performances of the users with high mobility.
Growth of Si and Ge nanostructures on Si substrates using ultrathin SiO/sub 2/ technology (2002)

Using scanning reflection electron microscopy and a high-temperature scanning tunneling microscopy (STM), we study the growth processes of Si and Ge nanostructures on Si substrates covered with ultrathin SiO/sub 2/ films. Si windows are formed in the ultrathin SiO/sub 2/ films by irradiating focused electron beams used for SREM or field emission electron beams from STM tips before or during heating samples. Ge nanoislands are grown only at the Si window positions by depositing Ge on the samples and by subsequent annealing of them. Moreover, Ge nanoislands about 7 nm in size and ultrahigh density (>10/sup 12//cm/sup 2/) are grown on the ultrathin SiO/sub 2/ films. These nanoislands can be manipulated by STM when they are separated from Si substrates by the ultrathin SiO/sub 2/ films. Si, Ge, Ge/Si and Si/Ge/Si nanoislands can also be grown on the Si windows by selective growth using Si/sub 2/H/sub 6/ and GeH/sub 4/ gases. These nanoislands are found to be stable on the Si windows during high-temperature annealing. These results indicate that ultrathin SiO/sub 2/ technology is useful for growing Si and Ge nanostructures on given areas.
Symmetry-recovering crises of chaos in polarization-related optical bistability (1984)

We investigate delay-induced chaos in an optically bistable system which has a symmetry with respect to the exchange of two circular polarizations. Roughly speaking, the output of the system bifurcates in the following way as the input light intensity increases: (1) symmetric steady state, (2) asymmetric steady state, (3) asymmetric periodic oscillation, (4) asymmetric chaos, and (5) symmetric chaos. The first bifurcation is a well-known symmetry-breaking transition. It is shown that the last bifurcation through which the symmetry is recovered can be viewed as a crisis of chaos, which has been defined by Grebogi et al. as a sudden change of strange attractor. By changing system parameters, we find three distinct types of the crises in the experiment with an electronic circuit which simulates the difference-differntial system equation. Before and after the crises, waveforms characteristic of each type are observed. In a simple two-dimensional-map model, we can find all three types of crises. It is also found that the types of crises are determined by the nature of unstable fixed (or periodic) points which cause the crises by colliding with the chaotic attractors. The symmetry-recovering crises seem to be general phenomena appearing in nonlinear systems with some symmetries.
Nonuniform Swelling of Alkali Swellable Microgels (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNonuniform Swelling of Alkali Swellable MicrogelsB. E. Rodriguez, M. S. Wolfe, and M. FrydCite this: Macromolecules 1994, 27, 22, 6642–6647Publication Date (Print):October 1, 1994Publication History Published online1 May 2002Published inissue 1 October 1994https://pubs.acs.org/doi/10.1021/ma00100a058https://doi.org/10.1021/ma00100a058research-articleACS PublicationsRequest reuse permissionsArticle Views692Altmetric-Citations102LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Effect of Tocilizumab vs Usual Care in Adults Hospitalized With COVID-19 and Moderate or Severe Pneumonia (2020)

ClinicalTrials.gov Identifier: NCT04331808.
Application of 1,3‐azomethine ylides derived from α‐dicarbonyl compounds and <scp>L</scp>‐proline to the synthesis of pyrrolizidines (2010)

Abstract magnified image The reaction of 2,3‐butanedione, ethyl pyruvate, and phenylglyoxal with β‐nitrostyrene and L ‐proline in isopropanol at room temperature gives substituted pyrrolizidines, as a result of one‐pot three component reaction. On the contrary, a spiropyrrolizidine is formed from 1,2‐cyclohexanedione only when the reaction is carried out in refluxing isopropanol, whereas at room temperature, incorporation of the amine component into the products is not observed and bicyclo[3.2.1]octanones are formed, as a result of a tandem Michael‐Henry reaction. In this latter case, L ‐proline acts as an organocatalyst, although with modest enantioselectivity. The stereochemistry of the products is given and the mechanism of formation of products is postulated, on the basis of stereochemical arguments. J. Heterocyclic Chem., (2010).
Time-Reversal Massive Multipath Effect: A Single-Antenna “Massive MIMO” Solution (2016)

The explosion of mobile data traffic calls for new efficient 5G technologies. Massive multiple-input multiple-output (MIMO), which has shown the great potential in improving the achievable rate with a very large number of antennas, has become a popular candidate. However, the requirement of deploying a large number of antennas at the base station may not be feasible in indoor scenarios due to the high implementation complexity. Does there exist a good alternative that can achieve similar system performance to massive MIMO for indoor environment? In this paper, we show that by using time-reversal (TR) signal processing, with a sufficiently large bandwidth, one can harvest the massive multipaths naturally existing in a rich-scattering environment to form a large number of virtual antennas and achieve the desired massive multipath effect with a single antenna. We answer the above question by analyzing the TR massive multipath effect and the achievable rate with some waveforms. We also derive the corresponding asymptotic achievable rate under a massive multipath setting. Experiment results based on real indoor channel measurements show that the massive multipaths can be revealed with a sufficiently large bandwidth in a practical indoor environment. Moreover, based on our experiments with real indoor measurements, the achievable rate of the TR wideband system is evaluated.
Lanthanide and boron oxide-coated <b>α</b>-Fe particles (1996)

To increase the coercivity of α-Fe particles, needlelike goethite crystals were first coated with different Ln3+ ions (Ln=La,Nd,Sm,Gd,Dy,Eu) plus B3+, then reduced to α-Fe under H2. The magnetic moment of the particles depends upon the Ln and B contents and temperature. Both powder x-ray diffraction and Mössbauer spectra indicate the existence of a crystalline FeO phase; the FeO content decreased as the reduction temperature increased. A phase with no hyperfine splitting was also detected in the Mössbauer spectra, which may be superparamagnetic α-Fe or amorphous iron oxide; the amount of this phase decreased as the reduction temperature increased. The temperature dependence of the coercivity of these B- and Ln-coated particles was steeper than for particles coated with silica: this suggests a coercivity mechanism other than shape anisotropy.
Conjugate addition reactions of .alpha.,.beta.-unsaturated ketones with higher order, mixed organocuprate reagents, R2Cu(CN)Li2 (1984)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConjugate addition reactions of .alpha.,.beta.-unsaturated ketones with higher order, mixed organocuprate reagents, R2Cu(CN)Li2Bruce H. Lipshutz, Robert S. Wilhelm, and Joseph A. KozlowskiCite this: J. Org. Chem. 1984, 49, 21, 3938–3942Publication Date (Print):October 1, 1984Publication History Published online1 May 2002Published inissue 1 October 1984https://pubs.acs.org/doi/10.1021/jo00195a010https://doi.org/10.1021/jo00195a010research-articleACS PublicationsRequest reuse permissionsArticle Views1490Altmetric-Citations80LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Development of human embryos to the hatched blastocyst stage in the presence or absence of a monolayer of Vero cells (1993)

In a prospective randomized study, excess embryos from 100 women undergoing in-vitro fertilization were cultured from the 2-cell to the hatched-blastocyst stage in the presence or absence of a confluent monolayer of Vero cells. The frequencies of fragmentation, developmental arrest, multinucleation and blastocyst formation were observed for 254 embryos over 7 days in culture. The number of nucleated cells, and fine structure of trophectoderm and inner cell mass were analysed at the expanded blastocyst stage on day 5.5 post-insemination. The frequency of hatching from the zona pellucida was determined between days 6 and 7 post-insemination. With respect to these developmental parameters, the findings indicate that no overt or statistically significant improvement in early human embryogenesis occurs in the co-culture system.
A Direct Synthesis Approach for Microwave Filters With a Complex Load and Its Application to Direct Diplexer Design (2007)

This paper presents a direct synthesis approach for general Chebyshev filters terminated with a complex load. The new approach is based on the fact that the polynomial functions for synthesizing the filters are composed for any matched loads. By normalizing the polynomial functions with assumed complex matched load impedance by a real reference load impedance using power waves normalization, a set of new polynomial functions for the same filter, but with real load impedance, can be formulated, from which the coupling matrix for the physical filter design can be obtained using a standard direct filter synthesis approach. This new direct synthesis approach can find many applications. A practical application is the direct diplexer design with a realistic junction model being taken into account. With the diplexer design is concerned, a fast-converged iterative scheme is proposed. The effectiveness and the validation of the proposed scheme are demonstrated by two design examples
Opposing roles of polycomb repressive complexes in hematopoietic stem and progenitor cells (2010)

Polycomb group (PcG) proteins are transcriptional repressors with a central role in the establishment and maintenance of gene expression patterns during development. We have investigated the role of polycomb repressive complexes (PRCs) in hematopoietic stem cells (HSCs) and progenitor populations. We show that mice with loss of function mutations in PRC2 components display enhanced HSC/progenitor population activity, whereas mutations that disrupt PRC1 or pleiohomeotic repressive complex are associated with HSC/progenitor cell defects. Because the hierarchical model of PRC action would predict synergistic effects of PRC1 and PRC2 mutation, these opposing effects suggest this model does not hold true in HSC/progenitor cells. To investigate the molecular targets of each complex in HSC/progenitor cells, we measured genome-wide expression changes associated with PRC deficiency, and identified transcriptional networks that are differentially regulated by PRC1 and PRC2. These studies provide new insights into the mechanistic interplay between distinct PRCs and have important implications for approaching PcG proteins as therapeutic targets.
Modular Construction: The Wave of the Future. (1989)

These results suggest that plasma TGF-beta levels during treatment may be useful to determine which patients are at high risk of developing symptomatic pneumonitis following thoracic radiotherapy. This finding may have implications when planning additional therapy (either chemotherapy or radiotherapy) which may have potentially adverse consequences on the lung.
Use of haploids and isozyme markers for genetic analysis in the polysomic polyploid potato -Ie (1993)

Hapluids (sporophytes with lhe gametic chrom06(Jme number) f,um polysomk: p(.Jlyploid~ represem a random gameti'c sample from the parenl and can be used 10 map genes that affect quantltat,ve trai! vmiation (OTV) with the aid of moleculm' markers (isozymes or RFLPs). The objel;ljvc: of (his work was to analyze QTV using isozyme markers in four potato (tetrasomic p0lyploid) haploid populations, Almost 200 haploids from lhe cvs. Chippewa', M,TrimRck' and the advanced S('kction W-231 were: evaluated ph~notypicaJJy for eight different agronomic traits and scored for 13 isozyme nll\rkers distributed in the 12 different linkage groups ot potatO, Eighl (lIZLI!,US ere linked 10 quanlolatilJ(' trait loci (QT~) affecting QTV on the traits evaluated, HOW(;:lcT, lhere welt: difference between haploid pupuJations for QTLs a.. . paren/. Three out of four QTLs for tuber yield and two out or lour QTLs tor avcrage tuber wci~ht, linked (0 isozyme markers in tht' Atlantic haploid population, had overdOnlmance as the main lypt: 01 g'.:Jjt' ;, ~osity on the phenotype and explains why the loss of parental heterozygosity, 01' the CliltiviJf Atlantic, results in lower than o.pcded tuber yield in its haploid progen)'. Key \\'()rds: Double reduction, Linkage maps, Molecular markers, QTLs, Solallum Il,beroswrl.
Microwave Drying of Wastewater Sewage Sludge (2013)

The purpose of this study was to investigate the effect of Microwave (MW) power levels (480 to 1080 W) and sample mass (90 to 150 g) on the drying characteristics of the sewage sludge. The drying tests were carried out using a modified domestic microwave unit with a process control system. The results showed that drying rate was directly proportional to the MW power, but inversely proportional to the sample mass. The desired temperature could be achieved in short period of time at higher power level. MW drying showed a significant increase (from 5.65 MJ/kg to 18.75 MJ/kg) in calorific value of sewage sludge.
The Gastrointestinal Tolerability of the LOX/COX Inhibitor, Licofelone, is Similar to Placebo and Superior to Naproxen Therapy in Healthy Volunteers: Results From a Randomized, Controlled Trial (2004)

The results from this trial indicate that licofelone has a potential gastrointestinal safety advantage over conventional NSAID therapy, as licofelone was associated with significantly superior gastric tolerability and a lower incidence of ulcers compared with naproxen in healthy volunteers. Further trials will be required to investigate the safety and efficacy of licofelone in the treatment of diseases such as osteoarthritis.
BIOMECHANICAL ASSESSMENT OF A NOVEL EXPANDABLE HIP SCREW VERSUS DYNAMIC HIP SCREW (2018)

Background The advantages of treatment by open reduction and internal fixation for intertrochanteric fractures of the proximal femur have been well known for several decades. Failure of fixation can result in revision surgery, prolonged inpatient stay and has major socio-economic consequences. There are many new devices on the market to help deal with this problem. Expandable hip screw (EHS) is one such device, which is an expanding bolt that may offer superior fixation in osteoporotic bone compared to the standard dynamic hip screw (DHS) type device. Methods Static axial compression tests with elastic deformation of the specimens were performed with a crosshead speed of 10 mm/min to determine stiffness of testing was performed with 3 cycles from 0 N to 250 N, 3 cycles from 0 N to 500 N, 3 cycles from 0 N to 750 N and 3 cycles from 0 N to 1000 N with a holding time of 10 s per test cycle. Displacement control was apply the pullout strength with a velocity of 1mm/sec. The ability to resist rotation about the axis of a lag screw is of critical importance particularly when the fracture line is perpendicular, or nearly perpendicular, to the femoral neck. Implants were subjected to a rotation of 1 degree/sec and peak torque values were recorded. Results The mean axial cyclic loading DHS showed higher stiffness value than EHS. The mean stiffness achieved at pullout test in the EHS and DHS groups were 587.8N/mm and, 334.1N/mm respectively (p Conclusions The EHS device demonstrated superior resistance to pullout and torsion greater loads compared to the DHS in an unstable fracture model. However, axial cyclic loading demonstrate lower strength, by optimising the size of device will perform. Level of Evidence Level 5
GaAs quantum well laser and heterojunction bipolar transistor integration using molecular beam epitaxial regrowth (1991)

To explore monolithically integrated phototransmitters, a graded-index quantum well laser was integrated with a selectivity regrown heterojunction bipolar transistor (HBT). The laser utilized a p-up configuration, and the HBT used collector down geometry. This scheme allowed the devices to be interconnected through the n+-GaAs substrate. The threshold current (Ith) for the ridge waveguide laser was ∼70 mA. The HBT exhibited a small signal gain of 26 at a collector current of 30 mA. The modulation index defined as the change in light output per unit change in base current is 1.2 mW/mA for our device.