gebhart/patrepeval huggingface dataset:
Numerical simulation of diffusion MRI signals using an adaptive time-stepping method (2013)

The effect on the MRI signal of water diffusion in biological tissues in the presence of applied magnetic field gradient pulses can be modelled by a multiple compartment Bloch-Torrey partial differential equation. We present a method for the numerical solution of this equation by coupling a standard Cartesian spatial discretization with an adaptive time discretization. The time discretization is done using the explicit Runge-Kutta-Chebyshev method, which is more efficient than the forward Euler time discretization for diffusive-type problems. We use this approach to simulate the diffusion MRI signal from the extra-cylindrical compartment in a tissue model of the brain gray matter consisting of cylindrical and spherical cells and illustrate the effect of cell membrane permeability.
Fine-electrode fabrication on Si surfaces: electrode process vs. hydrogenated surface preparation (2004)

A fabrication method of four-probe fine electrodes on a Si(100)-2×1-H surface was developed. The method involves conventional lithographic and scanning-probe nano-fabrication techniques followed by a high-temperature cleaning process of the surface. Using scanning tunneling microscopy, it was confirmed that a Si(100)-2×1-H surface was formed except for the fine electrode areas. Tunneling spectroscopy showed that the metallic feature remains on the electrode after the high-temperature cleaning process. To examine function of the electrodes, electrical transport measurements of a nanoscale silver wire were performed. The result exhibited significant conductance of the wire. From these results, it was concluded that the fabricated fine electrodes have the ability to measure electrical conduction of nanostructures fabricated on surfaces. [DOI: 10.1380/ejssnt.2004.160]
Deformation-Induced Anomalous Swelling of Topologically Disordered Gels (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDeformation-Induced Anomalous Swelling of Topologically Disordered GelsP. Pekarski, A. Tkachenko, and Y. RabinCite this: Macromolecules 1994, 27, 24, 7192–7196Publication Date (Print):November 1, 1994Publication History Published online1 May 2002Published inissue 1 November 1994https://pubs.acs.org/doi/10.1021/ma00102a030https://doi.org/10.1021/ma00102a030research-articleACS PublicationsRequest reuse permissionsArticle Views115Altmetric-Citations13LEARN 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
[Study on application of PCR in the diagnosis of Haemophilus influenzae pneumonia] (2002)

OBJECTIVE: To study the role of Haemophilus influenzae(Hi) in pneumonia and that of PCR in the diagnosis of Hi pneumonia. METHODS: Hi genus-specific PCR, Hib type-specific PCR and selective Hi culture media were used to detect 83 samples of deep nasal pharyngeal aspiration (NPA), 51 sera from 83 children younger than 3 years with pneumonia and 37 samples of pharyngeal swabs from healthy children. RESULTS: Of 83 NPA samples, 20(24.1 %) were positive by culture, 36 (43.4 %) positive by Hi-PCR and 19 (22.9 %) positive by Hib-PCR.Six out of 51 sera were positive by Hi-PCR and Hib-PCR, but none positive by culture. Of 37 pharyngeal swabs from healthy children, 3 ( 8.1 %) were positive by culture, 6 ( 16.2 %) positive by Hi-PCR and none positive by Hib-PCR. CONCLUSION: Hib-PCR is more appropriate for detecting NPA samples from children with pneumonia because of the high rate of non-typeable Hi carriers in healthy children.
GaN based nanorods for solid state lighting (2012)

In recent years, GaN nanorods are emerging as a very promising novel route toward devices for nano-optoelectronics and nano-photonics. In particular, core-shell light emitting devices are thought to be a breakthrough development in solid state lighting, nanorod based LEDs have many potential advantages as compared to their 2 D thin film counterparts. In this paper, we review the recent developments of GaN nanorod growth, characterization, and related device applications based on GaN nanorods. The initial work on GaN nanorod growth focused on catalyst-assisted and catalyst-free statistical growth. The growth condition and growth mechanisms were extensively investigated and discussed. Doping of GaN nanorods, especially p-doping, was found to significantly influence the morphology of GaN nanorods. The large surface of 3 D GaN nanorods induces new optical and electrical properties, which normally can be neglected in layered structures. Recently, more controlled selective area growth of GaN nanorods was realized using patterned substrates both by metalorganic chemical vapor deposition (MOCVD) and by molecular beam epitaxy (MBE). Advanced structures, for example, photonic crystals and DBRs are meanwhile integrated in GaN nanorod structures. Based on the work of growth and characterization of GaN nanorods, GaN nanoLEDs were reported by several groups with different growth and processing methods. Core/shell nanoLED structures were also demonstrated, which could be potentially useful for future high efficient LED structures. In this paper, we will discuss recent developments in GaN nanorod technology, focusing on the potential advantages, but also discussing problems and open questions, which may impose obstacles during the future development of a GaN nanorod based LED technology.
A VISUALIZATION AND FUSION SYSTEM FOR IMAGE GUIDED RFA PROCEDURES (2010)

We introduce a 3D visualization and fusion system to enhance the safety of Radio-Frequency Ablation (RFA) procedures by means of new concepts and techniques of data visualization. The developed system introduces a novel Collision Detection (CD) feature in order to avoid hitting major vessels and vital organs with the RFA probe. Intra-operative registration allows the fusion of image data for visual guidance during the insertion of the RFA probe in the abdomen. The proposed system has a component based design and architecture. This RFA system is integrated to support a complete interventional workflow. The system has been successfully used to develop different applications for RFA of liver tumors. The performance of the collision detection has been validated by experiments on a multi-modality abdominal phantom which have shown very good and accurate results.
Supported Nanometric Titanium Oxide Sols as a New Efficient Photocatalyst (2005)

We report on the first study of the photocatalytic performance of immobilized smallest titanium oxide oxoparticles of the size 2R = 5.0 nm on a glass support. The nanometric particles are prepared in the sol-gel reactor with rapid reagent mixing and temperature, atmosphere, and particle size control. The surface coverage is achieved by inserting the support into the reactor solution during the induction period, where chemically active nanoparticles are relatively stable. We show that this immobilized amorphous oxo phase of titanium oxide exhibits considerable activity toward photocatalytic degradation of trichloroethylene in the gas phase. Moreover, one of the important factors appears to be the catalyst surface preparation, which has to be free of the adsorbed alcohol molecules. UV-assisted exchange between propoxy and hydroxy groups is suggested as the surface activation mechanism. The film thickness is expected to strongly affect the material photocatalytic efficiency because of the internal traps population.
Frozen Cyclohexane-in-Water Emulsion as a Sacrificial Template for the Synthesis of Multilayered Polyelectrolyte Microcapsules (2009)

This paper reports the application of frozen cyclohexane-in-water emulsions as sacrificial templates for the fabrication of hollow microcapsules through layer-by-layer assembly of polyelectrolytes, poly(styrenesulfonate sodium salt), and poly(allylamine hydrochloride). Extraction of the cyclohexane phase from frozen emulsions stabilized with 11 polyelectrolyte layers by compatibilization with 30% v/v ethanol leads to the formation of water-filled microcapsules while preserving the spherical geometry. The majority of microcapsules (>90%) are prepared with intact polyelectrolyte membranes as measured by their deformation induced by osmotic pressure. This work provides a new route for the synthesis of hollow multilayered microcapsules under mild operating conditions.
Skewed genomic variability in strains of the toxigenic bacterial pathogen, Clostridium perfringens (2006)

Clostridium perfringens is a Gram-positive, anaerobic spore-forming bacterium commonly found in soil, sediments, and the human gastrointestinal tract. C. perfringens is responsible for a wide spectrum of disease, including food poisoning, gas gangrene (clostridial myonecrosis), enteritis necroticans, and non-foodborne gastrointestinal infections. The complete genome sequences of Clostridium perfringens strain ATCC 13124, a gas gangrene isolate and the species type strain, and the enterotoxin-producing food poisoning strain SM101, were determined and compared with the published C. perfringens strain 13 genome. Comparison of the three genomes revealed considerable genomic diversity with >300 unique "genomic islands" identified, with the majority of these islands unusually clustered on one replichore. PCR-based analysis indicated that the large genomic islands are widely variable across a large collection of C. perfringens strains. These islands encode genes that correlate to differences in virulence and phenotypic characteristics of these strains. Significant differences between the strains include numerous novel mobile elements and genes encoding metabolic capabilities, strain-specific extracellular polysaccharide capsule, sporulation factors, toxins, and other secreted enzymes, providing substantial insight into this medically important bacterial pathogen.
The Bioexpandable Prosthesis: A New Perspective After Resection of Malignant Bone Tumors in Children (2005)

Bone reconstruction after resection of malignant bone tumors of the lower extremity in children and adolescents remains a challenge in limb-sparing surgery. Equal limb length at maturity and good functional outcome are the main goals of these surgeries but often are difficult to achieve. Expandable endoprostheses are available but usually require repeated operative interventions for lengthening. Moreover, as the size of the implant increases, the proportion of the implant relative to the remaining bone increases, generating a biomechanical disadvantage to the limb. The authors describe a new concept combining an endoprosthesis with a fully implantable motorized distraction nail that can be activated in gradual steps to lengthen the remaining bone by callus distraction. New high-quality bone is growing and the proportion of prosthesis length compared with leg length develops in favor of the remaining bone.
A theoretical and numerical evaluation of the steady-state burning rate of vertically oriented PMMA slabs (2008)

The steady state burning rate of vertically oriented slabs of poly-methyl-methacrylate (PMMA) is numerically investigated. Model predictions are compared with measurements and results of the laminar boundary layer (LBL) theory. The numerical model provides a solution of the Favre-averaged Navier–Stokes equations coupled with sub-models for turbulence, combustion, soot production and radiation. The modelling of condensed phase processes is based on the one-dimensional heat transfer equation and pyrolysis is treated as a phase change using the latent heat approach. Results show that the pyrolysing region can be divided into three regions. In the laminar part of the flow (Gr x < 4.3 × 107), the predicted normalised burning rate, [mdot]″ p x/μ∞, is a power-law function of Gr x with an exponent close to that of the LBL theory, surface re-radiation being the primary source of discrepancies. From the LBL theory for free flow, it is demonstrated that the local burning rate is inversely proportional to the shear velocity gradient. This is globally confirmed by numerical model results. At Gr x = 4.3 × 107 the change in slope of the burning rate observed experimentally, which indicates the end of the laminar flow region, is reproduced numerically. From Gr x = 2.5 × 109 model results show that the surface mass flux of pyrolyzate increases with x, in agreement with experimental data in literature.
The Fibronectin Production Is Increased by Thrombospondin via Activation of TGF-β in Cultured Human Mesangial Cells (1998)

Thrombospondin (TSP) is a multifunctional glycoprotein that is synthesized by a variety of cells including mesangial cells (MCs). To clarify the effect of TSP on the pathogenesis of diabetic nephropathy, we studied the effect of glucose concentrations on TSP synthesis in cultured human MCs. Thereafter, the effects of TSP on the activation of transforming growth factor beta (TGF-beta) and fibronectin production were investigated in MCs. Incubating MCs with elevated glucose levels for 6 days resulted in an increase in TSP synthesis, measured by an enzyme-linked immunosorbent assay, both in culture media and cell layers. Treatment of MCs with TSP (final concentrations 1 and 5 microg/ml) for 24 h resulted in an increase (1.3- and 2.1-fold, respectively) in active TGF-beta, which was determined with an enzyme-linked immunosorbent assay using TGF-beta-soluble receptor type II, in the culture media without having any effect on the production of total TGF-beta. Exposure of MCs to TSP caused enhancement of fibronectin production in both media and cell layers in a TSP dose-dependent manner with the maximum at a TSP concentration of 1 microg/ml. The TSP-induced increase in fibronectin production from MCs was completely prevented by concomitant treatment with 10 microg/ml anti-TGF-beta neutralizing antibody. These results indicate that the TSP production is promoted by a high ambient glucose concentration in human MCs and that TSP, in turn, causes an increase in fibronectin production via activation of TGF-beta.
Advances in Spectral Optical Code-Division Multiple-Access Communications (2007)

Code-division multiple-access (CDMA) has flourished as a successful wireless networking technology in mobile cellular telephony, and wireless local area networks (LAN) such as the unlicensed industry, science, and medicine (ISM) bands. The commercial exploitation of the benefits of CDMA raises the question as to whether optical code-based communications offer significant benefits to an optical network and what are the technologies that enable code-based optical networks. Recent investigations of optical CDMA (OCDMA) strategies have addressed this question through numerous laboratory-based test-bed studies of multiuser link and recent experimental field trials conducted on in-the-ground fiber. OCDMA requires its own physical layer technologies that are distinctly different from widely pursued wavelength-division-multiplexed (WDM) all-optical networks. Simulations of multiuser performance predict ultimate link capacity and the performance of broadcast and select synchronous nets with strong central management as well as asynchronous architectures with reduced centralized management.
Evaluation of mixing of a secondary solid phase in a circulating fluidized bed riser (2023)

Mixing of the secondary solids phase, i.e. fuel or sorbent is crucial in fluidized bed reactors due to its effect on the performance of the reactor. Fluctuations in the gas-particle flow affect mixing, thus modeling this is essential for the analysis of mixing. However, simplified mixing models are used for large circulating fluidized bed (CFB) reactors, which causes uncertainties. A novel averaging method is presented to obtain representative results of transient secondary solid phase mixing in CFBs, acknowledging the effect of fluctuations. A parametric study is performed to investigate the effect of particle size, density, and inlet velocity on mixing and for insight into the mixing process. Additionally, the presented approach is used to compare different steady-state mixing methods to evaluate their applicability for modeling mixing in CFB reactors. Initial momentum and elutriation tendency of fuel were found to affect the mixing behavior, with two distinct routes identified.
Abnormalities of Chemotactic Lymphokine Synthesis and Mononuclear Leukocyte Chemotaxis in Wiskott-Aldrich Syndrome (1974)

Wiskott-Aldrich syndrome is characterized by numerous humoral and cellular immune abnormalities including anergy, defective antibody production, and increased immunoglobulin synthesis. To define better the mechanisms of defective cellular immunity in this disorder, lymphoproliferative responses, lymphokine production, and the chemotactic responsiveness of mononuclear leukocytes (MNL) from patients with Wiskott-Aldrich syndrome were quantitated. Peripheral blood lymphocytes from these patients produced normal amounts of a lymphocyte-derived chemotactic factor (LDCF); however, their lymphoproliferative responses were frequently depressed, particularly to antigenic stimuli. In the absence of exogenous antigens or mitogens, lymphocytes from patients with Wiskott-Aldrich syndrome produced significantly more LDCF than unstimulated normal lymphocytes. In fact, this unstimulated LDCF production frequently approached the level produced by normal cells only after antigen or mitogen stimulation. The chemotactic responsiveness of MNL from Wiskott-Aldrich syndrome patients was impaired, particularly in those patients with the highest rates of unstimulated LDCF production. Furthermore, normal MNL chemotactic responsiveness could be impaired by preincubation of these cells in either LDCF or plasma from Wiskott-Aldrich syndrome patients. These observations suggest that the regulation of LDCF synthesis is abnormal in Wiskott-Aldrich syndrome, and that a humoral chemotactic inhibitor, perhaps LDCF, "deactivates" the circulating MNL of patients with this syndrome.
Re-Designing of Existing Pharmaceuticals for Environmental Biodegradability: A Tiered Approach with β-Blocker Propranolol as an Example (2015)

Worldwide, contamination of aquatic systems with micropollutants, including pharmaceuticals, is one of the challenges for sustainable management of water resources. Although micropollutants are present at low concentrations, many of them raise considerable toxicological concerns, particularly when present as components of complex mixtures. Recent research has shown that this problem cannot be sustainably solved with advanced effluent treatment. Therefore, an alternative that might overcome these environmental problems is the design of new pharmaceutical molecules or the redesign of existing pharmaceutical molecules that present the functionality needed for their application and have improved environmental biodegradability. Such redesigning can be performed by small molecular changes in the drug molecule with intact drug moiety which could incorporate the additional attribute such as biodegradability while retaining its pharmacological potency. This proof of concept study provides an approach for the rational redesign of a given pharmaceutical (Propranolol as an example). New derivatives with small molecular changes as compared to propranolol molecule were generated by a nontargeted photolysis process. Generated derivatives with intact drug moieties (an aromatic ring and a β-ethanolamine moiety) were further screened for aerobic biodegradability and pharmacological potency. The feasibility of the approach of redesigning an existing pharmaceutical through nontargeted generation of new derivatives with intact drug moiety and through subsequent screening was demonstrated in this study. Application of such approaches in turn might contribute to the protection of water resources in a truly sustainable manner.
Commentary: The Authors Reply (1995)

Environmental and Occupational Health Sciences Institute, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey
Polyhalogenated heterocyclic compounds. Part 44. Reactions of perfluoro-(4-isopropylpyridine) with oxygen nucleophiles (2000)

Reactions between perfluoro-(4-isopropyl pyridine) 1 and a variety of oxygen nucleophiles gave mono, di-and tri-alkoxylated systems depending on reaction conditions. The barrier to rotation for the perfluoro-isopropyl group in several pyridine systems was measured by 19 F n.m.r. saturation transfer experiments.
Simultaneous transmit and receive performance of an 8-channel digital phased array (2017)

The Aperture-Level Simultaneous Transmit and Receive (ALSTAR) architecture enables extremely high isolation between adjacent transmitting and receiving sub-arrays in a digital phased array without analog cancellers or other complex front-end hardware. An eight-channel ALSTAR array prototype was constructed and demonstrated to achieve 140.5 dB effective isotropic isolation between broadside transmit and receive beams over a 100 MHz instantaneous band centered at 2.45 GHz. This material is based upon work supported by the Assistant Secretary of Defense for Research and Engineering under Air Force Contract No. FA8721-05-C-0002 and/or FA8702-15-D-0001. Any opinions, findings, conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Assistant Secretary of Defense for Research and Engineering.
Morphological stability, interfacial tension, and dual-phase continuity in polystyrene-polyethylene blends (1997)

The morphological stability of polystyrene high-density polyethylene (PS/PE) blend is investigated in the region of dual-phase continuity. The effect of the addition of a triblock SEBS copolymer to the blends on the stability of these morphologies, is examined. The results show that the morphology of the unmodified blends changes from co-continuous to droplet matrix for PS-rich blends whereas the morphology of a 50/50 blend maintains continuity but coarsened significantly upon annealing at 200°C. In the presence of the copolymer, these morphologies are much more stable. Selective solvent extraction of polystyrene in di-ethyl ether reveals that the level of PS continuity in the 50/50 blend is higher for the unmodified system than for the modified one. Upon annealing, the level of PS continuity significantly increases for the unmodified 50/50 PS/PE blend. The effect of the copolymer content in the blend on the interfacial tension between the two components is also investigated using the breaking thread method. The interfacial tension is found to be reduced from 5.6 to 1.1 mN/m by the addition of 20 parts of the copolymer to the blend. © 1997 John Wiley & Sons, Inc.