gebhart/patrepeval huggingface dataset:
Optically pumped blue organic semiconductor lasers (1998)

Lasing at 460, 485, and 510 nm is demonstrated in optically pumped, vacuum-deposited amorphous thin films of a carbazole derivative doped with Coumarin 47, perylene, and Coumarin 30, respectively. Efficient, nonradiative Förster energy transfer between host and dopant organic molecules results in low lasing thresholds (5 μJ/cm2), high differential quantum efficiencies (15%), high peak output powers (20 W), and long operational lifetimes (&gt;105 pulses at 100 times the threshold power).
Design of 3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde as a reagent for ultrasensitive determination of primary amines by capillary electrophoresis using laser fluorescence detection (1991)

Amino acids and peptides, from both standard solutions and biological samples, were successfully reacted with 3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde, at low concentration, to form highly fluorescent isoindole derivatives. The formed mixtures are effectively separated by high-performance capillary electrophoresis and their constituents detected by their laser-induced fluorescence signals. The minimum detectable quantities in the low attomole (10(-18) mol) range are encountered.
Magnetostimulation Limits in Magnetic Particle Imaging (2013)

For magnetic particle imaging (MPI), specific absorption rate (SAR) and more critically magnetostimulation (i.e., dB/dt) safety limits will determine the optimal scan parameters, such as the drive field strength and frequency. These parameters will impact the scanning speed, field-of-view (FOV) and signal-to-noise ratio in MPI. Understanding the potential safety hazards of the drive field is critical for scaling MPI for human use. In this work, we demonstrate that magnetostimulation is the primary magnetic safety consideration in MPI, and we describe the first human-subject magnetostimulation threshold experiments for MPI using homogeneous coils. Our experiments, performed on the arm and leg, indicate that magnetostimulation thresholds monotonically decrease with increasing frequency. Additionally, we show for the first time that a strong inverse correlation exists between the threshold and the body part size. The chronaxie time, on the other hand, did not vary with body part size. We conclude with an estimation of the magnetostimulation thresholds for a full-body MPI scanner: a mean asymptotic threshold of 14.3 mT-pp (peak-to-peak) with a mean chronaxie time of 289 μs, which correspond to a magnetostimulation threshold of about 15 mT-pp for frequencies between 25 and 50 kHz. These findings will have a great impact on the optimization of MPI parameters, especially in determining the number of partial FOVs required to cover a region of interest.
Process for preparation of large-particle-size monodisperse latexes (1981)

Monodisperse latexes having a particle size in the range of 2 to 40 microns are prepared by seeded emulsion polymerization in microgravity. A reaction mixture containing smaller monodisperse latex seed particles, predetermined amounts of monomer, emulsifier, initiator, inhibitor and water is placed in a microgravity environment, and polymerization is initiated by heating. The reaction is allowed to continue until the seed particles grow to a predetermined size, and the resulting enlarged particles are then recovered. A plurality of particle-growing steps can be used to reach larger sizes within the stated range, with enlarge particles from the previous steps being used as seed particles for the succeeding steps. Microgravity enables preparation of particles in the stated size range by avoiding gravity related problems of creaming and settling, and flocculation induced by mechanical shear that have precluded their preparation in a normal gravity environment.
Cancer chemopreventive activity mediated by 4'-bromoflavone, a potent inducer of phase II detoxification enzymes. (1999)

Induction of phase II enzymes is an important mechanism of chemoprevention. In our search for novel cancer chemopreventive agents, 4'-bromoflavone (4'BF) was found to significantly induce quinone reductase (QR) activity in cultured murine hepatoma 1c1c7 cells (concentration to double activity: 10 nM) and effectively induce the alpha- and mu-isoforms of glutathione S-transferase in cultured H4IIE rat hepatoma cells with no observed toxicity. In short-term dietary studies, 4'BF was also shown to increase QR activity and glutathione levels in rat liver, mammary gland, colon, stomach, and lung in a dose-dependent manner. Induction mediated by 4'BF was bifunctional (induction of both phase I and phase II enzymes) and regulated at the transcriptional level, as revealed by transient transfection studies with plasmid constructs (pDTD-1097CAT, XRE-CAT, and ARE-CAT) and reverse transcription-PCR-based analysis of QR mRNA. In studies conducted with female Sprague Dawley rats, the effects of 4'BF on the relative induction levels of phase I and phase II enzyme activities were investigated in liver and mammary gland. Treatment with 4'BF and 7,12-dimethylbenz[a]anthracene (DMBA) or 4'BF alone did not significantly alter DMBA-induced cytochrome P4501A1 activity (phase I enzyme), but it significantly increased QR activity (phase II enzyme), compared with the DMBA treatment group. In addition, 4'BF was found to be a potent inhibitor of cytochrome P4501A1-mediated ethoxyresorufin-O-deethylase activity, with an IC50 of 0.86 microM. Furthermore, in studies conducted with cultured HepG2 or MCF-7 cells, 4'BF significantly reduced the covalent binding of metabolically activated benzo[a]pyrene to cellular DNA. On the basis of these results, a full-term cancer chemoprevention study was conducted with DMBA-treated female Sprague Dawley rats. Dietary administration of 4'BF (2000 and 4000 mg per kg of diet, from 1 week before to 1 week after DMBA) significantly inhibited the incidence and multiplicity of mammary tumors and greatly increased tumor latency. In summary, 4'BF can be viewed as a relatively simple, readily available, inexpensive compound that is a highly effective cancer chemopreventive agent. The full mechanism of action remains to be defined, but enhancement of detoxification pathways appears to be important.
Fine-grained polysilicon films with built-in tensile strain (1988)

Novel processing conditions and strain diagnostic structures are used to demonstrate that polysilicon films with built-in tensile-strain can be achieved and that any physical size limitations due to compressive-buckling in polysilicon micromechanical structures can be eliminated.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Dynamic Distributed Threshold Control for Spatial Reuse in IEEE 802.11ax (2022)

The IEEE 802.11ax standard (Wi-Fi 6), among other features, adopts a feature called spatial reuse, where new transmissions can be carried out in presence of ongoing, interfering transmissions from nodes in an overlapping basic service set (OBSS). Specifically, a node can adjust its threshold for detecting the interference, by setting a parameter called OBSS Power-Detect level <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\text{OBSS}_{-}\text{PD}_{\text{level}})$</tex> . When a node hears an ongoing transmission from an OBSS node, if its received signal strength indicator (RSSI) is below the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> , the node is said to have a spatial reuse opportunity. The node can transmit at a limited transmit power (TX_PWR) during the spatial reuse opportunity. The feasible values of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> and TX_PWR must satisfy certain constraints laid out by the IEEE 802.11ax standard. In this work, we propose an algorithm that first obtains <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> thresholds for maximizing the number of spatial reuse opportunities, and then selects the one that minimizes the packet error rate among these <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> thresholds. The trade-off involved is the following: setting <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> to a high value increases the number of spatial reuse opportunities, but necessitates transmissions to be at lower transmit power (due to the constraint specified by the standard) resulting in higher packet error rates, and vice versa. The proposed algorithm dynamically varies <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> based on packet error rates. Via simulations, we show that the proposed dynamic algorithm performs better (in terms of achieving a higher throughput and a lower packet error rate) than a naive method which adopts a constant <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{OBSS}_{-}\text{PD}_{\text{level}}$</tex> threshold and the case when the spatial reuse is not adopted. When the spatial reuse is implemented using the proposed algorithm, we also explore the performance of different traffic models served using QoS queues having different priorities and transmission parameters.
Indirubin-3′-oxime stimulates chondrocyte maturation and longitudinal bone growth via activation of the Wnt/β-catenin pathway (2019)

Researchers have shown increased interest in determining what stimulates height. Currently, many children undergo precocious puberty, resulting in short stature due to premature closure of the growth plate. However, the current approach for height enhancement is limited to growth hormone treatment, which often results in side effects and clinical failure and is costly. Although recent studies have indicated the importance of paracrine signals in the growth plate for longitudinal bone growth, height-stimulating agents targeting the signaling pathways involved in growth plate maturation remain unavailable in the clinic. The Wnt/β-catenin pathway plays a major role in the maturation of growth plate chondrocytes. In this study, by using an ex vivo tibial culture system, we identified indirubin-3'-oxime (I3O) as a compound capable of enhancing longitudinal bone growth. I3O promoted chondrocyte proliferation and differentiation via activation of the Wnt/β-catenin pathway in vitro. Intraperitoneal injection of I3O in adolescent mice increased growth plate height along with incremental chondrocyte maturation. I3O promoted tibial growth without significant adverse effects on bone thickness and articular cartilage. Therefore, I3O could be a potential therapeutic agent for increasing height in children with growth retardation.
High‐Performance Supercapacitors Based on Hierarchically Porous Graphite Particles (2011)

Hierarchically porous graphite particles are synthesized using a continuous, scalable aerosol approach. The unique porous graphite architecture provides the particles with high surface area, fast ion transportation, and good electronic conductivity, which endows the resulting supercapacitors with high energy and power densities. This work provides a new material platform for high-performance supercapacitors with high packing density, and is adaptable to battery electrodes, fuel-cell catalyst supports, and other applications.
Synthesis and Activity of Substituted Anthraquinones against a Human Filarial Parasite, <i>Brugia </i><i>m</i><i>alayi</i> (2005)

Lymphatic filariasis (elephantiasis) is a global public health problem caused by the parasitic nematodes Wuchereria bancrofti and Brugia malayi. We have previously reported anthraquinones from daylily roots with potent activity against pathogenic trematode Schistosoma mansoni. Here we report the synthesis of novel anthraquinones A-S and their antifilrarial activity. Anthraquinones A-S were synthesized by a single-step Friedel-Crafts acylation reaction between phthalic anhydrides and substituted benzenes. The antifilarial properties of these synthetic anthraquinones were tested against microfilaria as well as adult male and female worms of B. malayi. The most active anthraquinone was K, which showed 100% mortality within 1, 5, and 3 days, respectively, against microfilaria and adult male and female worms at 5 ppm concentration. Albendazole, an oral drug currently used to treat parasitic infections, was used as a positive control. Methylated products of anthraquinones did not affect the microfilaria. Histological examination of treated adult female parasites showed most of the anthraquinones caused marked effects on intrauterine embryos.
Multiplex chromatin interaction analysis by signal processing and statistical algorithms (2019)

Abstract The single-molecule multiplex chromatin interaction data generated by emerging non-ligation-based 3D genome mapping technologies provide novel insights into high dimensional chromatin organization, yet introduce new computational challenges. We developed MIA-Sig ( https://github.com/TheJacksonLaboratory/mia-sig.git ), an algorithmic framework to de-noise the data, assess the statistical significance of chromatin complexes, and identify topological domains and inter-domain contacts. On chromatin immunoprecipitation (ChIP)-enriched data, MIA-Sig can clearly distinguish the protein-associated interactions from the non-specific topological domains.
Allocating bandwidth in the resilient packet ring networks by PI controller (2011)

The Resilient Packet Ring (RPR), defined under IEEE 802.17, has been proposed as a high-speed backbone technology for metropolitan area networks. RPR is introduced to mitigate the underutilization and unfairness problems associated with the current technologies, SONET and Ethernet, respectively. The key performance objectives of RPR are to achieve high bandwidth utilization, optimum spatial reuse on the dual rings, and fairness. The challenge is to design an algorithm that can react dynamically to the traffics in achieving these objectives. The RPR fairness algorithm is comparatively simple, but it poses some critical limitations that require further investigation and remedy. One of the major problems is that the amount of bandwidth allocated by the algorithm oscillates severely under unbalanced traffic scenarios. These oscillations are barrier to achieving spatial reuse and high bandwidth utilization. Moreover, the performance of the RPR fairness algorithm is very sensitive to the algorithm parameter settings. In this paper, we apply Control Theory to solve the fairness issue. We construct a PI controller to dynamically adjust the fair rate in order to eliminate the state of congestion and to converge to the optimal fair rate.
Progress and challenges of selective Farnesoid X Receptor modulation (2018)

Bile acids are amphipathic molecules that were previously known to serve as fat solubilizers in the intestine in postprandial conditions. In the last two decades, bile acids have been recognized as signaling molecules regulating energy metabolism pathways via, amongst others, the farnesoid X receptor (FXR). Upon bile acid activation, FXR controls expression of genes involved in bile acid, lipid, glucose and amino acid metabolism. In addition, FXR activation has been shown to limit the inflammatory response. The central role of FXR in various aspects of metabolism and inflammation makes FXR an attractive drug target for several diseases, such as obesity, metabolic syndrome, non-alcoholic steatohepatitis, cholestasis and chronic inflammatory diseases of the liver and intestine. However, most of the currently available compounds impact on all discovered FXR-mediated functions and may have, on top of beneficial effects, undesired biological actions depending on the disease. Therefore, research efforts are increasingly focused on the development of selective FXR modulators, i.e. selective bile acid receptor modulators (SBARMs), aimed at limiting the potential side-effects of conventional full FXR agonists upon chronic treatment. Here, we review the rationale for the design of SBARMs comprising dissociation between metabolic and inflammatory signaling, gene-selective and tissue-specific targeting. We discuss the potential structural mechanisms underlying the binding properties of dissociating ligands of FXR in light of ongoing efforts on the generation of dissociated ligands for otxher nuclear receptors, as well as their pharmacological and therapeutic potential.
Nanosecond pulsed electric fields mimic natural cell signal transduction mechanisms (2004)

Applications of nanosecond pulsed electric fields (nsPEF) to human cells and mammalian tissues indicate that, as the pulse durations and/or the electric field intensities decrease, effects on the plasma membrane decrease and effects in intracellular signal transduction mechanisms increase. NsPEFs that are below the threshold for electroporation-like effects on the plasma membrane mimic cell-signaling mechanisms that determine cell fate, depending on the nsPEF conditions and the cell type. At relatively high electric fields, cell-signaling mechanisms are activated to induce death by apoptosis in cells and tumors. At electric fields below the threshold for apoptosis, nsPEFs induce calcium release from intracellular stores that mimic physiologic ligand effects on IP3-dependent calcium channels in the endoplasmic reticulum and subsequent capacitative calcium influx activated by store operated calcium channels (SOCC) in plasma membranes. In human platelets, nsPEF-induced calcium mobilization mimics thrombin-induced platelet activation and aggregation, a natural mechanism to clot blood and heal wounds. Thus, nsPEFs recruit intracellular signaling mechanisms, providing a new technology to modulate cell function for potential therapeutic and/or diagnostic applications in the future
The pesticides endosulfan, toxaphene, and dieldrin have estrogenic effects on human estrogen-sensitive cells. (1994)

Estrogenic pesticides such as DDT and chlordecone generate deleterious reproductive effects. An "in culture" bioassay was used to assess the estrogenicity of several pesticides. The E-screen test uses human breast estrogen-sensitive MCF7 cells and compares the cell yield achieved after 6 days of culture in medium supplemented with 5% charcoal-dextran stripped human serum in the presence (positive control) or absence (negative control) of estradiol and with diverse concentrations of xenobiotics suspected of being estrogenic. Among the organochlorine pesticides tested, toxaphene, dieldrin, and endosulfan had estrogenic properties comparable to those of DDT and chlordecone; the latter are known to be estrogenic in rodent models. The E-screen test also revealed that estrogenic chemicals may act cumulatively; when mixed together they induce estrogenic responses at concentrations lower than those required when each compound is administered alone.
The NS3 Helicase and NS5B-to-3′X Regions Are Important for Efficient Hepatitis C Virus Strain JFH-1 Replication in Huh7 Cells (2007)

The JFH-1 strain of hepatitis C virus (HCV) is a genotype 2a strain that can replicate autonomously in Huh7 cells. The J6 strain is also a genotype 2a strain, but its full genomic RNA does not replicate in Huh7 cells. However, chimeric J6/JFH-1 RNA that has J6 structural-protein-coding regions and JFH-1 nonstructural-protein-coding regions can replicate autonomously and produce infectious HCV particles. In order to determine the mechanisms underlying JFH-1 RNA replication, we constructed various J6/JFH-1 chimeras and tested their RNA replication and virus particle production abilities in Huh7 cells. Via subgenomic-RNA-replication assays, we found that both the JFH-1 NS5B-to-3'X (N5BX) and the NS3 helicase (N3H) regions are important for the replication of the J6CF replicon. We applied these results to full-length genomic RNA replication and analyzed replication using Northern blotting. We found that a chimeric J6 clone with JFH-1 N3H and N5BX could replicate autonomously but that a chimeric J6 clone with only JFH-1 N5BX had no replication ability. Finally, we tested the virus production abilities of these clones and found that a chimeric J6 clone with JFH-1 N3H and N5BX could produce infectious HCV particles. In conclusion, the JFH-1 NS3 helicase and NS5B-to-3'X regions are important for efficient replication and virus particle formation of HCV genotype 2a strains.
The multiply-detected macrodiversity scheme for wireless cellular systems (1998)

The multiply-detected macrodiversity (MDM) scheme is proposed for wireless cellular systems. As opposed to the traditional macrodiversity schemes, in which at any time a signal from only one base station is selected, in the MDM scheme there is no selection, but all the received signals are detected, and a maximum-likelihood decision algorithm is employed to maximize the probability of correct decision. We study the performance of the MDM scheme and compare it with the performance of the traditional selection-based macrodiversity schemes. Depending on the propagation parameters, our results show that through the use of the MDM scheme, significant improvement in the bit-error rate (BER) can be achieved. For instance, if the outage probability is defined as BER above 10/sup -4/ the outage is eliminated at least 45% of the time as compared with signal-to-interference (S/I) diversity, for a propagation attenuation exponent of 4.0 and shadowing standard deviation of 4.0 dB. Furthermore, as compared with the (S/I) diversity, the MDM scheme reduces, on the average, the BER at least two orders of magnitude throughout more than 60% of the cell area for a propagation attenuation exponent of 3.5, shadowing standard deviation of 4.0 dB and system loading of less than 50%.
An MR fingerprinting approach for quantitative inhomogeneous magnetization transfer imaging (2021)

Purpose Magnetization transfer (MT) and inhomogeneous MT (ihMT) contrasts are used in MRI to provide information about macromolecular tissue content. In particular, MT is sensitive to macromolecules, and ihMT appears to be specific to myelinated tissue. This study proposes a technique to characterize MT and ihMT properties from a single acquisition, producing both semiquantitative contrast ratios and quantitative parameter maps. Theory and Methods Building on previous work that uses multiband RF pulses to efficiently generate ihMT contrast, we propose a cyclic steady‐state approach that cycles between multiband and single‐band pulses to boost the achieved contrast. Resultant time‐variable signals are reminiscent of an MR fingerprinting acquisition, except that the signal fluctuations are entirely mediated by MT effects. A dictionary‐based low‐rank inversion method is used to reconstruct the resulting images and to produce both semiquantitative MT ratio and ihMT ratio maps, as well as quantitative parameter estimates corresponding to an ihMT tissue model. Results Phantom and in vivo brain data acquired at 1.5 Tesla demonstrate the expected contrast trends, with ihMT ratio maps showing contrast more specific to white matter, as has been reported by others. Quantitative estimation of semisolid fraction and dipolar T 1 was also possible and yielded measurements consistent with literature values in the brain. Conclusion By cycling between multiband and single‐band pulses, an entirely MT‐mediated fingerprinting method was demonstrated. This proof‐of‐concept approach can be used to generate semiquantitative maps and quantitatively estimate some macromolecular‐specific tissue parameters.