gebhart/patrepeval huggingface dataset:
Barium titanate nanocrystals and nanocrystal thin films: Synthesis, ferroelectricity, and dielectric properties (2006)

Advanced applications for high k dielectric and ferroelectric materials in the electronics industry continues to demand an understanding of the underlying physics in decreasing dimensions into the nanoscale. We report the synthesis, processing, and electrical characterization of thin (&lt;100nm thick) nanostructured thin films of barium titanate (BaTiO3) built from uniform nanoparticles (&lt;20nm in diameter). We introduce a form of processing as a step toward the ability to prepare textured films based on assembly of nanoparticles. Essential to this approach is an understanding of the nanoparticle as a building block, combined with an ability to integrate them into thin films that have uniform and characteristic electrical properties. Our method offers a versatile means of preparing BaTiO3 nanocrystals, which can be used as a basis for micropatterned or continuous BaTiO3 nanocrystal thin films. We observe the BaTiO3 nanocrystals crystallize with evidence of tetragonality. We investigated the preparation of well-isolated BaTiO3 nanocrystals smaller than 10nm with control over aggregation and crystal densities on various substrates such as Si, Si∕SiO2, Si3N4∕Si, and Pt-coated Si substrates. BaTiO3 nanocrystal thin films were then prepared, resulting in films with a uniform nanocrystalline grain texture. Electric field dependent polarization measurements show spontaneous polarization and hysteresis, indicating ferroelectric behavior for the BaTiO3 nanocrystalline films with grain sizes in the range of 10–30nm. Dielectric measurements of the films show dielectic constants in the range of 85–90 over the 1KHz–100KHz, with low loss. We present nanocrystals as initial building blocks for the preparation of thin films which exhibit highly uniform nanostructured texture and grain sizes.
Neutral glycosphingolipids of the globo-series characterize activation stages corresponding to germinal center B cells (1990)

The neutral glycosphingolipid (GSL) globotriaosylceramide (Gb3) of the globo-series was recently defined as the CD77 antigen. This B cell-associated antigen is characterized by its specific expression on germinal center B cells. In order to study the potential relation of the CD77 antigen and other GSLs to B cell activation we have performed a comprehensive analysis of the synthesis and expression of neutral GSL in tonsillar B lymphocytes. Monoglycosylceramide (GL1) and lactosylceramide (LacCer) comprised the largest portion of GSL in tonsillar B lymphocytes as detected by HPLC analysis. GSLs of the globo-series Gb3 and globotetraosylceramide (Gb4), were found in smaller amounts. Since other GSLs, like gangliotriaosylceramide (Gg3) and gangliotetraosylceramide (Gg4), could only be detected using highly sensitive antibody reactions, we assume that these GSLs occur in B cells only in minor amounts. When tonsillar B cells were density fractionated on Percoll, the light density cells, which correspond to activated cells, contained and expressed more of both globo-GSLs than cells in the higher density fraction. When the dense fraction of tonsillar B cells was activated in vitro by anti-mu/BCGF, synthesis of GL1, LacCer, Gb3, and Gb4 was biphasic, with maxima at 12 and 84 h. Surface expression of the CD77 antigen on the denser cells was strongly induced by anti-mu/BCGF during the first 24 h of cultivation followed by a rapid decline thereafter, mimicking synthesis. PMA treatment of this cell fraction caused an even stronger expression of the CD77 antigen, which lasted over 48 h of cultivation.(ABSTRACT TRUNCATED AT 250 WORDS)
Uniformity optimization techniques for rapid thermal processing systems (2001)

This paper presents two efficient robust methods for uniformity optimization of rapid thermal processes. Both of these methods involve the reuse of empirical response surfaces linking zone powers to measured process data created on a baseline system. The first method uses fossilized gain matrices from the baseline system, while the second method involves customization of the baseline response surface for each system. The approaches use the response surfaces for iterative modification of zone powers to reduce the process nonuniformity on successively processed wafers. These methods are applied to the optimization of rapid thermal oxidation processes on several lamp-heated rapid thermal processing systems. Most of the uniformity improvement is obtained with the first two optimization runs; in some instances, the process is optimized to less than 1% 1-sigma nonuniformity with the use of just two wafers. Because the response surfaces from the baseline system can be reused for all similar systems, considerable savings in time and wafers are realized.
ZnO film based surface acoustic wave micro-pump (2007)

In this study, a micro-pump unit based on surface acoustic wave (SAW) on piezoelectric ZnO film is designed and fabricated as a micro-fluidic device. It employs a mechanical wave, which is generated electrically using an aluminum interdigital transducer (IDT), and propagates on the surface of the ZnO film. The ZnO film was used in this study because it has a high electromechanical coefficient and an excellent bonding with various substrate materials, in particular silicon. The sputtering parameters for ZnO film deposition have been optimized, and the ZnO films with different thickness from 1 micron to 5.5 microns were prepared. The film properties have been characterized using different methods, such as scanning electron microscopy, X-ray diffraction and atomic force microscopy. Aluminum IDT with a finger width and spacing of 8 microns was patterned on the ZnO film using a lift-off process. The frequency generated was measured using a network analyzer, and it varies from 130 MHz to 180 MHz as a function of film thickness. A signal generator was used to generate the frequency with a power amplifier to amplify the signal, which was then applied to aluminum IDT to generate the surface acoustic wave. If a liquid droplet exists on the surface carrying the acoustic wave, the energy and the momentum of the SAW will be coupled into the fluid, causing the liquid to vibrate and move on film surface. The strength of this movement is determined by the applied voltage and frequency. The volume of the liquid drop loaded on the SAW device in this study is of several hundreds of nanoliters. The movement of the liquid inside the droplet and also on the ZnO film surface can be demonstrated. The performance of ZnO SAW device was characterized as a function of film thickness.
New low-CTE ultrahigh-thermal-conductivity materials for lidar laser diode packaging (2005)

Laser diode packaging affects reliability, power level and weight (mass). Traditional thermal management materials - copper, copper/tungsten, copper/molybdenum, etc. - all have serious deficiencies. In the last few years there have been revolutionary thermal management material advances. There are now over 15 low-CTE, low-density materials having thermal conductivities that range from that of copper (400 W/m-K) to four times that of copper (1600 W/m-K). They are being used in an increasing number of commercial and aerospace applications. Some are low cost. Others have low cost potential in high volumes. Several are space qualified. This paper discusses the large and increasing number of advanced thermal management materials, including properties, applications, space qualification, cost, lessons learned, how to use composites to fix manufacturing problems, and future directions, including nanocomposites.
Mental Dysfunction and Resource Use in Nursing Homes (1993)

The role of dementia and other mental disorders in nursing home case-mix classification systems has been an area of controversy. The role of mental dysfunctions was considered in developing a new case-mix measurement system for facility payment in a national demonstration to understand staff time use in nursing homes. Nursing staff (nurses and aides) time and resident assessment data were collected for 6,663 nursing home residents in 6 states. Measures of signs and symptoms of cognitive impairment (dementia), depression, and delirium were created based on items from the new National Minimum Data Set. These measures then were used to determine whether mental dysfunctions were predictive of resource use (nursing staff times and costs) when controlling for other case-mix variables. Cognitive impairment was associated with slightly higher staff time only in less physically-impaired residents without serious medical conditions and not receiving heavy rehabilitation. Similarly, depression and delirium were associated with higher resource use only in selected types of residents. Based on these findings, the new Resource Utilization Groups Version III (RUG-III) contain a major category of residents who are cognitively impaired but not severely dependent in Activities of Daily Living. Depression is used to differentiate subgroups of residents with major medical conditions such as hemiplegia and aphasia. Delirium, when used together with other resident characteristics, was not found useful in explaining resource use. Case-mix groups defined by mental dysfunctions can foster improved care, but careful consideration must be given to appropriate incentives and documentation requirements for providers.
Development of a wake vortex spacing system for airport capacity enhancement and delay reduction (2002)

The Terminal Area Productivity project has developed the technologies required (weather measurement, wake prediction, and wake measurement) to determine the aircraft spacing needed to prevent wake vortex encounters in various weather conditions. The system performs weather measurements, predicts bounds on wake vortex behavior in those conditions, derives safe wake spacing criteria, and validates the wake predictions with wake vortex measurements. System performance to date indicates that the potential runway arrival rate increase with AVOSS, considering common path effects and ATC delivery variance, is 5% to 12% depending on the ratio of large and heavy aircraft. The concept demonstration system, using early generation algorithms and minimal optimization, is performing the wake predictions with adequate robustness such that only 4 "hard exceedances" have been observed in 1235 wake validation cases. This performance demonstrates the feasibility of predicting wake behavior bounds with multiple uncertainties present, including the unknown aircraft weight and speed, weather persistence between the wake prediction and the observations, and the location of the weather sensors several kilometers from the approach location. A concept for the use of the AVOSS system for parallel runway operations has been suggested, and an initial study at the JFK International Airport suggests that a simplified AVOSS system can be successfully operated using only a single lidar as both the weather sensor and the wake validation instrument. Such a self-contained AVOSS would be suitable for wake separation close to the airport, as is required for parallel approach concepts such as SOIA.
Defining and Measuring Traffic Data Quality: White Paper on Recommended Approaches (2004)

Recent research and analyses have identified several issues about the quality of traffic data available from intelligent transportation systems for transportation operations, planning, or other functions. FHWA contracted with Battelle, the Texas Transportation Institute, and Cambridge Systematics to develop an action plan to help stakeholders address traffic data quality issues. The project team developed a series of three white papers that addressed traffic data quality issues, and regional stakeholder workshops were held in Columbus, Ohio, and Salt Lake City, Utah, to critique the white papers and gather input for the traffic data quality action plan. Recommendations are provided for defining and measuring traffic data quality. Data quality is defined as "the fitness of data for all purposes that require it. Measuring data quality requires an understanding of all intended purposes for that data." Six key data quality measures are recommended: accuracy, completeness, validity, timeliness, coverage, and accessibility. Although examples and definitions of these data quality measures are given, future work will more clearly define the calculation and use of these data quality measures in different application areas of transportation.
Integrated Nutrient Management in Rice–Wheat Cropping System: An Evidence on Sustainability in the Indian Subcontinent through Meta-Analysis (2019)

Over years of intensive cultivation and imbalanced fertilizer use, the soils of the Indian subcontinent have become deficient in several nutrients and are impoverished in organic matter. Recently, this region has started emphasizing a shift from inorganic to organic farming to manage soil health. However, owing to the steadily increasing demands for food by the overgrowing populations of this region, a complete shift to an organic farming system is not possible. The rice–wheat cropping system (RWCS) is in crisis because of falling or static yields. The nations of this region have already recognized this problem and have modified farming systems toward integrated nutrient management (INM) practices. The INM concept aims to design farming systems to ensure sustainability by improving soil health, while securing food for the population by improving crop productivity. Therefore, this paper was synthesized to quantify the impact and role of INM in improving crop productivity and sustainability of the RWCS in the context of the Indian subcontinent through meta-analysis using 338 paired data during the period of 1989–2016. The meta-analysis of the whole data for rice and wheat showed a positive increase in the grain yield of both crops with the use of INM over inorganic fertilizers only (IORA), organic fertilizers only (ORA), and control (no fertilizers; CO) treatments. The increase in grain yield was significant at p < 0.05 for rice in INM over ORA and CO treatments. For wheat, the increase in grain yield was significant at p < 0.05 in INM over IORA, ORA, and CO treatments. The yield differences in the INM treatment over IORA were 0.05 and 0.13 Mg ha−1, respectively, in rice and wheat crops. The percent yield increases in INM treatment over IORA, ORA, and CO treatments were 2.52, 29.2, and 90.9, respectively, in loamy soil and 0.60, 24.9, and 93.7, respectively, in clayey soil. The net returns increased by 121% (INM vs. CO) in rice, and 9.34% (INM vs. IORA) and 127% (INM vs. CO) in wheat crop. Use of integrated nutrient management had a positive effect on soil properties as compared to other nutrient management options. Overall, the yield gain and maintenance of soil health due to INM practices over other nutrient management practices in RWCS can be a viable nutrient management option in the Indian subcontinent.
Polyethylenimine-sodium iodide complexes (1985)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolyethylenimine-sodium iodide complexesC. K. Chiang, G. T. Davis, C. A. Harding, and Toru TakahashiCite this: Macromolecules 1985, 18, 4, 825–827Publication Date (Print):April 1, 1985Publication History Published online1 May 2002Published inissue 1 April 1985https://pubs.acs.org/doi/10.1021/ma00146a043https://doi.org/10.1021/ma00146a043research-articleACS PublicationsRequest reuse permissionsArticle Views238Altmetric-Citations42LEARN 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
Transforming growth factor beta (TGF-beta), a potent inhibitor of erythropoiesis: neutralizing TGF-beta antibodies show erythropoietin as a potent stimulator of murine burst-forming unit erythroid colony formation in the absence of a burst-promoting activity (1995)

Transforming growth factor beta (TGF-beta) is a bifunctional regulator of the growth of myeloid progenitors and is here demonstrated to directly inhibit the growth of primitive erythroid progenitors by 95% to 100% regardless of the cytokines stimulating growth. Autocrine TGF- beta production of primitive hematopoietic progenitors has previously been reported. In the present study, a neutralizing TGF-beta antibody (anti-TGF-beta) added to serum-containing cultures, resulted in a 3-, 4- , and 25-fold increase in burst-forming unit erythroid (BFU-E) colony formation in response to interleukin-4 (IL-4) plus erythropoietin (Epo), SCF plus Epo, and IL-11 plus Epo, respectively. The growth of BFU-E progenitors has been suggested to require a burst-promoting activity in addition to Epo. Accordingly, we observed no BFU-E colony formation in serum-containing cultures in response to Epo alone. In contrast, 50 BFU-E colonies were formed when anti-TGF-beta was included in the culture. In serum-free cultures, Epo also stimulated BFU-E colony formation in the absence of other cytokines, whereas anti-TGF- beta had no effect on the number of colonies formed. Quantitation of TGF-beta 1 in serum by an enzyme-linked immunosorbent assay method showed predominantly the presence of precursor (latent) TGF-beta 1, but also showed active TGF-beta 1 at a concentration sufficient to potently inhibit erythroid colony formation. Thus, neutralization of active TGF- beta 1 in serum shows that Epo alone is sufficient to stimulate the growth of murine BFU-E progenitors.
Radiologic application of a microcomputer-based three-dimensional imaging system. (1992)

March 1992Radiologic application of a microcomputer-based three-dimensional imaging system.Authors: J R Crass, A M Cohen, and S D MironAuthor Info & AffiliationsVolume 158, Issue 3https://doi.org/10.2214/ajr.158.3.1739019 METRICS PDFotherformats
Comparison of the Crystal Structures and Magnetic Properties of the Low- and High-Temperature Forms of AgCuPO<sub>4</sub>:  Crystal Structure Determination, Magnetic Susceptibility Measurements, and Spin Dimer Analysis (2006)

The crystal structure of the low-temperature form of AgCuPO4 (i.e., alpha-AgCuPO4) was determined by powder X-ray diffraction and was compared with that of the high-temperature form of AgCuPO4 (i.e., beta-AgCuPO4). The magnetic properties of the two forms were examined by measuring their magnetic susceptibilities and evaluating the relative strengths of their spin-exchange interactions on the basis of spin-dimer analysis. Both forms of AgCuPO4 have layers of Cu2P2O8 alternating with silver-atom double layers; beta-AgCuPO4 has two Cu2P2O8 layers per unit cell, while alpha-AgCuPO4 has one. The coordinate environment of each Cu2+ ion is close to being a distorted square pyramid in alpha-AgCuPO4, but it is close to being a distorted trigonal bipyramid in beta-AgCuPO4. The magnetic susceptibilities of alpha- and beta-AgCuPO4 are well simulated by an antiferromagnetic alternating-chain model, which leads to J/k(B) = -146.1 K and alphaJ/k(B) = -75.8 K for alpha-AgCuPO4, and J/k(B) = -82.6 K and alphaJ/k(B) = -31.7 K for beta-AgCuPO4 (with the convention in which the spin-exchange parameter between two adjacent spin sites is written as 2J). The spin gaps, delta/k(B), obtained from these parameters are 93.7 K for alpha-AgCuPO4 and 62.3 K for beta-AgCuPO4. The strongest spin exchange in both forms of AgCuPO4 comes from a super-superexchange path, and this interaction is stronger for alpha-AgCuPO4 than for beta-AgCuPO4 by a factor of approximately 2, in good agreement with the experiment. Our analysis supports the use of this model for beta-AgCuPO4 and indicates that the spin lattice of alpha-AgCuPO4 would be better described by a two-dimensional net made up of weakly interacting alternating chains.
Joint<i>L</i><sup>1</sup>and total variation regularization for fluorescence molecular tomography (2012)

Fluorescence molecular tomography (FMT) is an imaging modality that exploits the specificity of fluorescent biomarkers to enable 3D visualization of molecular targets and pathways in vivo in small animals. Owing to the high degree of absorption and scattering of light through tissue, the FMT inverse problem is inherently ill-conditioned making image reconstruction highly susceptible to the effects of noise and numerical errors. Appropriate priors or penalties are needed to facilitate reconstruction and to restrict the search space to a specific solution set. Typically, fluorescent probes are locally concentrated within specific areas of interest (e.g., inside tumors). The commonly used L(2) norm penalty generates the minimum energy solution, which tends to be spread out in space. Instead, we present here an approach involving a combination of the L(1) and total variation norm penalties, the former to suppress spurious background signals and enforce sparsity and the latter to preserve local smoothness and piecewise constancy in the reconstructed images. We have developed a surrogate-based optimization method for minimizing the joint penalties. The method was validated using both simulated and experimental data obtained from a mouse-shaped phantom mimicking tissue optical properties and containing two embedded fluorescent sources. Fluorescence data were collected using a 3D FMT setup that uses an EMCCD camera for image acquisition and a conical mirror for full-surface viewing. A range of performance metrics was utilized to evaluate our simulation results and to compare our method with the L(1), L(2) and total variation norm penalty-based approaches. The experimental results were assessed using the Dice similarity coefficients computed after co-registration with a CT image of the phantom.