gebhart/patrepeval huggingface dataset:
Engineering bone‐like tissue <i>in vitro</i> using human bone marrow stem cells and silk scaffolds (2004)

Porous biodegradable silk scaffolds and human bone marrow derived mesenchymal stem cells (hMSCs) were used to engineer bone-like tissue in vitro. Two different scaffolds with the same microstructure were studied: collagen (to assess the effects of fast degradation) and silk with covalently bound RGD sequences (to assess the effects of enhanced cell attachment and slow degradation). The hMSCs were isolated, expanded in culture, characterized with respect to the expression of surface markers and ability for chondrogenic and osteogenic differentiation, seeded on scaffolds, and cultured for up to 4 weeks. Histological analysis and microcomputer tomography showed the development of up to 1.2-mm-long interconnected and organized bonelike trabeculae with cuboid cells on the silk-RGD scaffolds, features still present but to a lesser extent on silk scaffolds and absent on the collagen scaffolds. The X-ray diffraction pattern of the deposited bone corresponded to hydroxyapatite present in the native bone. Biochemical analysis showed increased mineralization on silk-RGD scaffolds compared with either silk or collagen scaffolds after 4 weeks. Expression of bone sialoprotein, osteopontin, and bone morphogenetic protein 2 was significantly higher for hMSCs cultured in osteogenic than control medium both after 2 and 4 weeks in culture. The results suggest that RGD-silk scaffolds are particularly suitable for autologous bone tissue engineering, presumably because of their stable macroporous structure, tailorable mechanical properties matching those of native bone, and slow degradation.
Hot-stage for <i>i</i> <i>n</i> <i>s</i> <i>i</i> <i>t</i> <i>u</i> operation of a battery in a scanning electron microscope (1984)

A hot-stage assembly has been designed, built, and operated inside a scanning electron microscope to observe and study the electrode–electrolyte interface behavior of a sodium–sulfur cell. This device has demonstrated the possibility of direct observation of the sodium evolution process onto the surface of a sodium beta″-alumina electrolyte. The results illustrated the wetting behavior of liquid sodium with the electrolyte surface and the dynamic behavior of liquid sodium evolution processes.
Making large-scale nyström approximation possible (2010)

The Nyström method is an efficient technique for the eigenvalue decomposition of large kernel matrices. However, in order to ensure an accurate approximation, a sufficiently large number of columns have to be sampled. On very large data sets, the SVD step on the resultant data submatrix will soon dominate the computations and become prohibitive. In this paper, we propose an accurate and scalable Nyström scheme that first samples a large column subset from the input matrix, but then only performs an approximate SVD on the inner submatrix by using the recent randomized low-rank matrix approximation algorithms. Theoretical analysis shows that the proposed algorithm is as accurate as the standard Nyström method that directly performs a large SVD on the inner submatrix. On the other hand, its time complexity is only as low as performing a small SVD. Experiments are performed on a number of large-scale data sets for low-rank approximation and spectral embedding. In particular, spectral embedding of a MNIST data set with 3.3 million examples takes less than an hour on a standard PC with 4G memory. Copyright 2010 by the author(s)/owner(s).
Structural tunability and switchable exciton emission in inorganic-organic hybrids with mixed halides (2013)

Room-temperature tunable excitonic photoluminescence is demonstrated in alloy-tuned layered Inorganic-Organic (IO) hybrids, (C12H25NH3)2PbI4(1−y)Br4y (y = 0 to 1). These perovskite IO hybrids adopt structures with alternating stacks of low-dimensional inorganic and organic layers, considered to be naturally self-assembled multiple quantum wells. These systems resemble stacked monolayer 2D semiconductors since no interlayer coupling exists. Thin films of IO hybrids exhibit sharp and strong photoluminescence (PL) at room-temperature due to stable excitons formed within the low-dimensional inorganic layers. Systematic variation in the observed exciton PL from 510 nm to 350 nm as the alloy composition is changed, is attributed to the structural readjustment of crystal packing upon increase of the Br content in the Pb-I inorganic network. The energy separation between exciton absorption and PL is attributed to the modified exciton density of states and diffusion of excitons from relatively higher energy states corresponding to bromine rich sites towards the lower energy iodine sites. Apart from compositional fluctuations, these excitons show remarkable reversible flips at temperature-induced phase transitions. All the results are successfully correlated with thermal and structural studies. Such structural engineering flexibility in these hybrids allows selective tuning of desirable exciton properties within suitable operating temperature ranges. Such wide-range PL tunability and reversible exciton switching in these novel IO hybrids paves the way to potential applications in new generation of optoelectronic devices.
Purification and Properties of Extracellular Glucosyltransferase Synthesizing 1,6-, 1,3- -D-Glucan from Streptococcus mutans Serotype a (1985)

An extracellular glucosyltransferase (sucrose: 1,6-, 1,3-alpha-D-glucan 3-alpha- and 6-alpha-D-glucosyltransferase, EC 2.4.1.-) of Streptococcus mutans HS6 (serotype a) was purified from culture supernatant by DEAE-Sepharose chromatography and preparative isoelectric focusing. The molecular weight measured by SDS-PAGE was 159 000 and the isoelectric point was pH 4.9. The specific activity was 89.7 i.u. (mg protein)-1 and the optimum pH was 6.0. The Km value for sucrose was 4.9 mM and the enzyme activity was not stimulated by exogenous dextran T10. Glucan was synthesized de novo from sucrose by the purified enzyme and consisted of 49.1 mol% 1,6-alpha-linked glucose and 33.9 mol% 1,3-alpha-linked glucose, with 13.6 mol% terminal glucose and 3.3 mol% 1,3,6-alpha-branched glucose.
Large-Scale Oligonucleotide Synthesis Using the Solid-Phase Approach (2003)

Synthetic DNA of defined sequences are commonly termed “oligonucleotides,” which are primarily composed of four different types of nucleosides linked through well-defined deoxyribose phosphate. Over the past ten years, because of refinement in synthesis chemistries (1a–1e) and automation of synthesis steps (2a,2b), oligonucleotide syntheses of defined sequences are common practices in nonchemists’ laboratories. Oligonucleotides are routinely used as DNA sequencing primers (3a–3c), probes (4a, 4b), linkers, adaptors, and gene synthesis (5). In addition to these applications, biophysical studies (6a,6b) (NMR, X-ray crystallography) for structural information of synthetic oligonucleotide using milligram quantities have been carried out. Newer applications of oligonucleotides are also emerging in the field of clinical diagnosis (7a–7c), forensic testing, and disease treatment (8a–8e). Investigations are being carried out in many laboratories for potential use of oligonucleotides as therapeutic agents broadly referred to as “use as antisense DNA.” Inhibition of viral replication in diseases, such as AIDS, herpes, and human pepiloma virus, and regulation of oncogene expression with oligonucleotides or their analogs are two major potential applications of synthetic DNA. Presently, these studies are moving out of research laboratories and into practical medical applications (9).
The Arthritic Diathesis and Epilepsy [Arthritisme et Épilepsie]. (Ann. Méd. Psych., March, <i>1926</i>.) Pasturel, M. (1927)

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An open access repository of images on plant health to enable the development of mobile disease diagnostics (2015)

Human society needs to increase food production by an estimated 70% by 2050 to feed an expected population size that is predicted to be over 9 billion people. Currently, infectious diseases reduce the potential yield by an average of 40% with many farmers in the developing world experiencing yield losses as high as 100%. The widespread distribution of smartphones among crop growers around the world with an expected 5 billion smartphones by 2020 offers the potential of turning the smartphone into a valuable tool for diverse communities growing food. One potential application is the development of mobile disease diagnostics through machine learning and crowdsourcing. Here we announce the release of over 50,000 expertly curated images on healthy and infected leaves of crops plants through the existing online platform PlantVillage. We describe both the data and the platform. These data are the beginning of an on-going, crowdsourcing effort to enable computer vision approaches to help solve the problem of yield losses in crop plants due to infectious diseases.
Exito muy especial de la exposición de Valls 2010 (2010)

Twenty-eight patients were included in a double-blind placebo-controlled study of a vaccine containing tyrosine-adsorbed Dermatophagoides pteronyssinus antigen (Migen(R)). The aim of the trial was to show the efficacy and safety of Migen as a 6-injection course, with or without a follow-up course of 6 maintenance doses, for the treatment of bronchial asthma. The patients selected had suffered from perennial asthma for at least 2 years and gave a strong skin reaction to house dust mite. The subjects in the study were divided into two groups: one of twelve patients receiving only a standard course of six graded injections at weekly intervals and the other of sixteen patients receiving the same course followed by a maintenance course comprising six injections of the highest strength (400 N.U.). Approximately half the patients in each of these groups were on placebo. Assessment was based on the patient's and doctor's impression of the response to the treatment using a daily symptom record card and clinical observation of the patient at regular intervals. The overall assessment was graded in accordance with the following four point scale: very good, good, same and worse. Results showed that the pa tients receiving Migen as a 6-injection course responded better than patients receiving placebo; moreover, patients who received 6 maintenance injections of Migen gave a very good or good response compared to those who were submitted to 12 injections of placebo and also compared to those receiving the standard course. Particular notice was taken of the side effects of the vaccine. Migen proved to be a good and and safe method of treating bronchial asthma due to house dust mite (D. pteronyssinus).
Mining knowledge-sharing sites for viral marketing (2002)

Viral marketing takes advantage of networks of influence among customers to inexpensively achieve large changes in behavior. Our research seeks to put it on a firmer footing by mining these networks from data, building probabilistic models of them, and using these models to choose the best viral marketing plan. Knowledge-sharing sites, where customers review products and advise each other, are a fertile source for this type of data mining. In this paper we extend our previous techniques, achieving a large reduction in computational cost, and apply them to data from a knowledge-sharing site. We optimize the amount of marketing funds spent on each customer, rather than just making a binary decision on whether to market to him. We take into account the fact that knowledge of the network is partial, and that gathering that knowledge can itself have a cost. Our results show the robustness and utility of our approach.
Broad-range real time PCR and DNA sequencing for the diagnosis of bacterial meningitis (2005)

Rapid aetiological diagnosis of bacterial meningitis is crucial for the early targeting of antimicrobial and adjuvant therapy. Broad-range polymerase chain reaction (PCR) targeting the 16S rRNA gene allows aetiological diagnosis of bacterial meningitis when applied to cerebrospinal fluid (CSF). We assessed the additional diagnostic effect of applying a novel broad-range real time PCR and subsequent DNA sequencing to culture, microscopy, and broad-range conventional PCR on CSF in patients with suspected bacterial meningitis. Broad-range conventional PCR and broad-range real time PCR with subsequent DNA sequencing were applied to 206 CSF specimens collected consecutively from 203 patients aged 6 d to 86 y. Patients' charts were reviewed for clinical information. 17 pathogens were identified by PCR and DNA sequencing or culture. Three specimens were negative by culture but positive by broad-range real time PCR. Three specimens were positive by culture but negative by broad-range real time PCR. Compared with culture, the sensitivity of broad-range real time PCR was 86%, and the specificity 98%. Conventional PCR resulted in a sensitivity of 64% and specificity of 98%. Broad-range real time PCR was generally comparable to culture of CSF and may be a useful supplement, particularly when antimicrobial therapy has been administered. Broad-range real time PCR was more sensitive than broad-range conventional PCR and microscopy.
Off-line temporal analysis of hard real-time applications (2002)

The most critical part in the development of hard real-time applications is the priority mapping carried out with nonformal methods. Our approach is based on the view that if the real-time application software is transformed into a set of tasks modeled by proper temporal characteristics, then the schedule analysis is easier to be determined. We propose simple environment models (language and real-time kernel) and a methodology of temporal modeling of the application starting from initial task configuration and going through to a set of periodic tasks sharing critical resources. This configuration allows us to make off-line timing proofs by using well-known scheduling algorithms based either on static priority like rate monotonic or on dynamic priority like earliest deadline. The resource requirements of tasks are performed with the priority ceiling scheduling protocol. The proposed temporal analysis permits us to evaluate different temporal properties of the real-time application.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Diversity of the bacterial community in the rice rhizosphere managed under conventional and no-tillage practices (2013)

Bacterial diversity in the rice rhizosphere at different rice growth stages, managed under conventional and no-tillage practices, was explored using a culture-based approach. Actinobacteria are among the bacterial phyla abundant in the rice rhizosphere. Their diversity was further examined by constructing metagenomic libraries based on the 16S rRNA gene, using actinobacterial- and streptomycete-specific polymerase chain reaction (PCR) primers. The study included 132 culturable strains and 125 clones from the 16S rRNA gene libraries. In conventional tillage, there were 38% Proteobacteria, 22% Actinobacteria, 33% Firmicutes, 5% Bacteroidetes, and 2% Acidobacteria, whereas with no-tillage management there were 63% Proteobacteria, 24% Actinobacteria, 6% Firmicutes, and 8% Bacteroidetes as estimated using the culture-dependent method during the four stages of rice cultivation. Principal coordinates analysis was used to cluster the bacterial communities along axes of maximal variance. The different growth stages of rice appeared to influence the rhizosphere bacterial profile for both cultivation practices. Novel clones with low similarities (89-97%) to Actinobacteria and Streptomyces were retrieved from both rice fields by screening the 16S rRNA gene libraries using actinobacterial- and streptomycete-specific primers. By comparing the actinobacterial community retrieved by culture-dependent and molecular methods, it was clear that a more comprehensive assessment of microbial diversity in the rice rhizosphere can be obtained using a combination of both techniques than by using either method alone. We also succeeded in culturing a number of bacteria that were previously described as unculturable. These were in a phylogenetically deep lineage when compared with related cultivable genera.
Nanoparticle Coating for Advanced Optical, Mechanical and Rheological Properties (2007)

Abstract Primary titania nanoparticles were coated with ultrathin alumina films using Atomic Layer Deposition (ALD). The deposited films were highly uniform and conformal with an average growth rate of 0.2 nm per coating cycle. The alumina films eliminated the surface photocatalytic activity of titania nanoparticles, while maintained their original extinction efficiency of ultraviolet light. Deposited films provided a physical barrier that effectively prevented the titania surface from oxidizing organic material whereas conserving its bulk optical properties. Parts fabricated from coated powders by pressureless sintering had a 13 % increase in surface hardness over parts similarly fabricated from uncoated particles. Owing to its homogeneous distribution, the secondary alumina phase suppressed excessive grain growth. Alumina films completely reacted during sintering to form aluminum titanate composites, as verified by XRD. Coated particles showed a pseudoplastic behavior at low shear rates due to modified colloidal forces. This behavior became similar to the Newtonian flow of uncoated nanoparticle slurries as the shear rate increased. Suspensions of coated particles also showed a decreased viscosity relative to the viscosity of uncoated particle suspensions.
Macro model updating by global inversion of CFP operators (1996)

PreviousNext No AccessSEG Technical Program Expanded Abstracts 1996Macro model updating by global inversion of CFP operatorsAuthors: Rob F. HeggeJacob T. FokkemaRob F. HeggeSection of Applied Geophysics, Centre for Technical Geoscience, Delft University of Technology and Jacob T. FokkemaSection of Applied Geophysics, Centre for Technical Geoscience, Delft University of Technologyhttps://doi.org/10.1190/1.1826747 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Permalink: https://doi.org/10.1190/1.1826747FiguresReferencesRelatedDetailsCited byTomography of diffraction-based focusing operatorsLuiz Alberto Santos, Webe Joao Mansur, and George A. McMechan24 August 2012 | GEOPHYSICS, Vol. 77, No. 5 SEG Technical Program Expanded Abstracts 1996ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 1996 Pages: 2106 publication data© 1996 Copyright © 1996 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 10 Feb 2005 CITATION INFORMATION Rob F. Hegge and Jacob T. Fokkema, (1996), "Macro model updating by global inversion of CFP operators," SEG Technical Program Expanded Abstracts : 707-710. https://doi.org/10.1190/1.1826747 Plain-Language Summary PDF DownloadLoading ...
Ventricular Dynamics in Atrial Fibrillation (1957)

During atrial fibrillation there are beat-to-beat changes of ventricular rate, end-diastolic volume, end-diastolic pressure, and arterial pressure or resistance to ventricular ejection. The effect of these variables on left ventricular dynamics in man has been approached by studying single sequences of beats in patients with atrial fibrillation. An index of changes of left ventricular volume has been determined from the electrokymogram of left cardiac border. Left ventricular pressures have been measured at surgery or by the transbronchial technic. These studies provide a better understanding of the hemodynamics of the left ventricle during atrial fibrillation and demonstrate another approach to the study of left ventricular function in man.
Enhanced Delivery of siRNA to Retinal Ganglion Cells by Intravitreal Lipid Nanoparticles of Positive Charge (2020)

RNAi therapy has been developed and explored for treating retinal conditions since last decades. The progression of retinal diseases including the age-related macular degeneration and glaucoma is associated with the malfunction of specific retinal cells. Therefore, to deliver therapeutic RNAi to selective retinal tissues with desired gene downregulation is crucial for the treatment of retinal diseases <i>via</i> RNAi therapy. Lipid-based nanoparticles are potent delivery vectors for RNAi therapeutics to achieve high gene silencing efficiency. The surface charge has been demonstrated to affect the intraocular behaviors and retinal distribution of intravitreally administered lipid nanoparticles (LNPs), which could subsequently affect the gene knockdown efficiency in specific retinal layers. Here, we evaluated three charged LNPs for their ability to deliver siRNA and facilitate gene downregulation both <i>in vitro</i> and <i>in vivo</i>. LNPs with different surface charges ranging from neutral to positive (5-34 mV) were successfully formulated. All types of charged LNPs managed gene knockdown in both mammalian cell line and primary neurons. At 48 h post intravitreal injection, neutral LNPs (6.2 mV) and mildly positive LNPs (15.9 mV) mediated limited retinal gene suppression (<10%) and the more positive LNPs (31.2 mV) led to ∼25% gene suppression in the retinal ganglion cell (RGC) layer. No gene silencing in the retinal pigmented epithelium layer was facilitated by any LNPs independent of the charges. In summary, this study has shown that positive LNPs with an optimized charge managed specific gene downregulation in the RGC layer. These RNAi carriers hold potential for the treatment of RGC-associated retinal diseases.
Cholinergic induction of oscillations in the hippocampal slice in the slow (0.5-2 Hz), theta (5-12 Hz), and gamma (35-70 Hz) bands (2000)

Carbachol, a muscarinic receptor agonist, produced three distinct spontaneous oscillations in the CA3 region of rat hippocampal slices. Carbachol concentrations in the 4-13 microM range produced regular synchronized CA3 discharges at 0.5-2 Hz (carbachol-delta). Higher concentrations (13-60 microM) produced short episodes of 5-10 Hz (carbachol-theta) oscillations separated by nonsynchronous activity. Concentrations of carbachol ranging from 8-25 microM also produced irregular episodes of high-frequency discharges (carbachol-gamma, 35-70 Hz), in isolation or mixed with carbachol-theta and carbachol-delta. At carbachol concentrations sufficient to induce carbachol-theta, low concentrations of APV reversibly transformed carbachol-theta into carbachol-delta. Higher concentrations of D,L-2-amino-5-phosphonopentanoic acid (APV) reversibly and completely blocked carbachol-theta. A systematic study of the effects of carbachol shows that the frequency of spontaneous oscillations depended nonlinearly on the level of muscarinic activation. Field and intracellular recordings from CA1 and CA3 pyramidal cells and interneurons during carbachol-induced rhythms revealed that the hippocampal circuitry preserved in the slice was capable of spontaneous activity over the range of frequencies observed in vivo and suggests that the presence of these rhythms could be under neuromodulatory control.
Shaping modes in multicore photonic crystal fibers (2005)

We explore the possibility of devising custom-shaped modes for multicore photonic crystal fibers by manipulating their geometrical structures. We present a recipe for constructing custom-shaped modes based on perturbation theory of coupled modes and the finite element method.