gebhart/patrepeval huggingface dataset:
Proposal for the biologically active conformation of opiates and enkephalin. (1977)

A model for the opiate receptor has been defined by using a computer-based molecular display and x-ray crystallographic input data. The model can explain the stereochemical fashion in which the morphine, morphinan, and oripavine classes of compounds interact with the receptor. The minimal structural unit of the enkephalins demonstrated to be pharmacologically active. Tyr-Gly-Gly-Phe, was also fitted to this model by using a systematic search of conformational space.
Multiresponsive microgels integration onto lab-on-fiber devices (2019)

Microgel assisted lab-on-fiber optrodes, arising from the integration of multiresponsive microgels onto nanostructured optical fibers tip, are emerging as intriguing multifunctional devices exploitable in biomedical applications, especially for label-free molecule detection. We have recently demonstrated that the sensitivity range of these devices is strictly related to the microgel films characteristics, which can be controlled during the microgel deposition procedure, based on the dip coating technique. With the aim of optimizing the deposition procedure in terms of fabrication throughput, we evaluate each fabrication step (fiber dipping, rinsing, and drying), demonstrating that the overall deposition duration can be significantly reduced from 960 min (of the ‘standard’ procedure) to 31 min, without affecting the microgel film characteristics. The analysis has been carried out by means of both optical and morphological characterization, and validated through repeatability tests. Overall, our results set the stage for engineering microgel assisted miniaturized optrodes, enabling their possible exploitation in industrial applications.
Rotenone‐induced caspase 9/3‐independent and ‐dependent cell death in undifferentiated and differentiated human neural stem cells (2005)

We used human neural stem cells (hNSCs) and their differentiated cultures as a model system to evaluate the mechanism(s) involved in rotenone (RO)- and camptothecin (CA)-induced cytotoxicity. Results from ultrastructural damage and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining indicated that RO-induced cytotoxicity resembled CA-induced apoptosis more than H(2)O(2)-induced necrosis. However, unlike CA-induced, caspase 9/3-dependent apoptosis, there was no increased activity in caspase 9, caspase 3 or poly (ADP-ribose) polymerase (PARP) cleavage in RO-induced cytotoxicity, in spite of time-dependent release of cytochrome c and apoptosis-inducing factor (AIF) following mitochondrial membrane depolarization and a significant increase in reactive oxygen species generation. Equal doses of RO and CA used in hNSCs induced caspase 9/3-dependent apoptosis in differentiated cultures. Time-dependent ATP depletion occurred earlier and to a greater extent in RO-treated hNSCs than in CA-treated hNSCs, or differentiated cultures treated with RO or CA. In conclusion, these results represent a unique ultrastructural and molecular characterization of RO- and CA-induced cytotoxicity in hNSCs and their differentiated cultures. Intracellular ATP levels may play an important role in determining whether neural progenitors or their differentiated cells follow a caspase 9/3-dependent or -independent pathway in response to acute insults from neuronal toxicants.
Pellet bed reactor for nuclear propelled vehicles: Part 1: Reactor technology (1991)

The pellet bed reactor (PBR) for nuclear propelled vehicles is briefly discussed. Much of the information is given in viewgraph form. Viewgraphs include information on the layout for a Mars mission using a PBR nuclear thermal rocket, the rocket reactor layout, the fuel pellet design, materials compatibility, fuel microspheres, microsphere coating, melting points in quasibinary systems, stress analysis of microspheres, safety features, and advantages of the PBR concept.
Document Examination by Laser (1987)

We have assessed the ability of laser-excited fluorescence to distinguish between similar inks, as might be found in document alterations. We find that the combined use of a coating procedure that strongly increases fluorescence efficiency at room temperature and fluorescence examination at 77°K provide high discriminatory capability. The procedures are easy to use and satisfy practicality requirements essential for utilization in document sections of law enforcement agencies.
A Radiofluorinated Divalent Cystine Knot Peptide for Tumor PET Imaging (2014)

A divalent knottin containing two separate integrin binding epitopes (RGD) in the adjacent loops, 3-4A, was recently developed and reported in our previous publication. In the current study, 3-4A was radiofluorinated with a 4-nitrophenyl 2-(18)F-fluoropropinate ((18)F-NFP) group and the resulting divalent positron emission tomography (PET) probe, (18)F-FP-3-4A, was evaluated as a novel imaging probe to detect integrin αvβ3 positive tumors in living animals. Knottin 3-4A was synthesized by solid phase peptide synthesis, folded, and site-specifically conjugated with (18/19)F-NFP to produce the fluorinated peptide (18/19)F-fluoropropinate-3-4A ((18/19)F-FP-3-4A). The stability of (18)F-FP-3-4A was tested in both phosphate buffered saline (PBS) buffer and mouse serum. Cell uptake assays of the radiolabeled peptides were performed using U87MG cells. In addition, small animal PET imaging and biodistribution studies of (18)F-FP-3-4A were performed in U87MG tumor-bearing mice. The receptor targeting specificity of the radiolabeled peptide was also verified by coinjecting the probe with a blocking peptide cyclo(RGDyK). Our study showed that (18)F-FP-3-4A exhibited excellent stability in PBS buffer (pH 7.4) and mouse serum. Small animal PET imaging and biodistribution data revealed that (18)F-FP-3-4A exhibited rapid and good tumor uptake (3.76 ± 0.59% ID/g and 2.22 ± 0.62% ID/g at 0.5 and 1 h, respectively). (18)F-FP-3-4A was rapidly cleared from the normal tissues, resulting in excellent tumor-to-normal tissue contrasts. For example, liver uptake was only 0.39 ± 0.07% ID/g and the tumor to liver ratio was 5.69 at 1 h p.i. Furthermore, coinjection of cyclo(RGDyK) with (18)F-FP-3-4A significantly inhibited tumor uptake (0.41 ± 0.12 vs 1.02 ± 0.19% ID/g at 2.5 h) in U87MG xenograft models, demonstrating specific accumulation of the probe in the tumor. In summary, the divalent probe (18)F-FP-3-4A is characterized by rapid and high tumor uptake and excellent tumor-to-normal tissue ratios. (18)F-FP-3-4A is a highly promising knottin based PET probe for translating into clinical imaging of tumor angiogenesis.
Modeling, fabrication and testing of MEMS tunable inductors varied with piezoelectric actuators (2014)

Modeling, fabrication and measurements of tunable inductors are presented where inductance tuning is achieved through mechanical displacement, by piezoelectric actuation, of mutually-coupled coils. The modified Greenhouse method is utilized as a modeling tool to predict the inductance variations as a function of both translation and angular displacement, where coils and traces which are arbitrarily oriented with respect to one another are considered. The use of this modeling approach is verified through experimental results where electrical measurements of inductances are compared with the modeled inductances. The inductance model compares well with the measurements and within 10% of the measured inductance with a 3% mean error. In addition, the impact of the interconnect widths on tunable inductor performances is assessed for both negatively and positively coupled tunable inductor cases, where devices with interconnect widths ranging between 10 and 40 µm are considered. Tuning ratios as high as ~3.9:1 were measured for the negatively-coupled coil designs with 18 V actuation; this corresponds to minimum and maximum quality factors of 5.72 (at 4.05 GHz with a 2.80 nH inductance) and 14.91 (at 2.25 GHz with 10.86 nH inductance), respectively. For the positively coupled inductors, tuning ratios of ~1.2:1 resulted with inductance and peak quality factors of 7.70 nH and ~18 (3.69 GHz), respectively. With 18 V actuation, these values tune to 6.57 nH with a Q ~18 (4.46 GHz). Residual poling stress was found to limit the practical tuning ratio to ~1.8:1 for the negatively coupled coils.
MEMS Based Multibeam Ion Linacs (2019)

We report on the development of multi-beam RF linear ion accelerators that are formed from stacks o low cost wafers. Wafers are prepared using MEMS techniques. We have demonstrated acceleration of ions in a 3x3 beamlet array with ion currents in the 0.1 mA range and acceleration at the 10 keV in lattice of RF (13 MHz) acceleration units and electrostatic quadrupoles. We will describe the status and plans for scaling to 10x10 beams, ion currents &gt;1 mA and ion energies &gt;100 keV in a compact, low cost setup for applications in materials processing.
Comprehensive Study of Risk Factors for Fatal Pedestrian Crashes in Urban Setup in a Developing Country (2020)

In developing nations, pedestrian safety is a matter of major concern. The present study investigates historical crash data (2011–2016) obtained from Kolkata police, India, and identifies the key risk factors for fatal pedestrian crashes at the road network level (i.e., intersections and midblock crossings). To develop an understanding of the risk factors associated with fatal pedestrian crashes, a set of safety performance functions (SPF) are developed for both intersection and midblock level. In these SPFs, several attempts are executed to identify a host of risk factors ranging from road infrastructure to land use, traffic exposure, and operational parameters, pedestrian-level attributes, and spatial characteristics of the road network. Based on the study outcomes, there is strong evidence that approaching speed of vehicles, pedestrian-vehicular volume ratio, overtaking tendency of vehicles, inaccessibility of pedestrian crosswalk, land use type, lower post-encroachment time (PET), longer waiting time before crossing, a high share of “pedestrian is not following zebra crossing,” pedestrians’ perceived crossing difficulty, the presence of “pedestrian attraction zone” (e.g., hospital, educational institute, shopping mall, bars, etc.), and high population density significantly affect the fatal pedestrian crash frequency at the intersection level. On the other hand, over-speeding and overtaking tendency of vehicles, inadequate pavement marking, lack of visibility during night-time, lower PET, higher crossing difficulty, longer waiting time before crossing, and several spatial features such as slum population and the presence of “pedestrian attraction zone”, significantly increase the likelihood of fatal pedestrian crashes at the midblock level.
Two dimensional multiwavelets with vanishing moments for image coding (2002)

A method for wavelet image coding and compression using a two-dimensional (2D) multiwavelet transform, vector quantization and zerotree coding techniques, is presented. A non-separable multiwavelet transform is used. The application of this approach results in 2D wavelet functions and filter-banks that are more suitable for coding of two-dimensional signals, such as images, than the traditional separable transform. We present nonlinear constraints on the polyphase matrix components which must be satisfied while imposing the requirement of vanishing moments. Finally, the design of 2D multiwavelets with a preferred orientation is illustrated.
Microwave signal transmission with high-speed InGaAsP lasers (1987)

High-speed semiconductor lasers are necessary components in new directly modulated fiber-optic communications systems including presently available 1.7-Gb/s systems, 3,4-Gb/s systems under development, 8-Gb/s NRZ research demonstrations over 30 km of fiber, pseudorandom modulation experiments at 8-Gb/s RZ and 10-Gb/s NRZ, and 16-Gb/s NRZ simulations using comb generators. High-speed lasers and detectors are also needed for new fiber-optic microwave signal transmission systems which have very significant advantages over their coaxial cable and waveguide counterparts, namely, low loss, large bandwidth, lightweight and flexible cable, and immunity to interception and electromagnetic interference. New optical components make system bandwidths of 10-20 GHz possible and should allow narrowband systems to operate at carrier frequencies to at least 30 GHz.
Large Capacitor Defibrillation Waveform Reduces Peak Voltages Without Increasing Energies (1995)

The 500 microF, long duration waveform reduced peak voltage 41% (374 +/- 18 V [STD] vs 219 +/- 14 V [LD], P < 0.001) and reduced peak current 38% (11.0 +/- 1.1 A [STD] vs 6.8 +/- 0.6 A [LD], P < 0.001) but did not significantly change the delivered energy (12.4 +/- 1.3 J [STD] vs 13.4 +/- 1.0 J [LD]). Durations increased from 10.0 +/- 0.2 to 17.6 +/- 0.5 msec (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
Gain Fixed Pattern Noise Correction via Optical Flow (2004)

The paper describes a method that uses a video sequence to correct gain fixed pattern noise (FPN) in an image sensor. The captured sequence and its optical flow are used to estimate gain FPN. Assuming brightness constancy along the motion trajectories, the pixels are grouped in blocks and the gains of the pixels in each block are estimated by iteratively minimizing the sum of the squared brightness variations along the motion trajectories. Significant reductions in gain FPN are demonstrated using both real and synthetically generated video sequences with modest computations.
Mononucleoside SATE Glucosyl Phosphorothiolates as a New Series of Pronucleotides (2004)

Abstract For Abstract see ChemInform Abstract in Full Text.
Domain nucleation and growth of La0.7Ca0.3MnO3−δ/LaAlO3 films studied by low temperature magnetic force microscopy (2003)

The field-dependent domain structure of epitaxial La0.7Ca0.3MnO3−δ thin films grown on a LaAlO3(001) substrate has been studied as a function of film thickness (50 and 100 nm) and oxygen content (optimum and deficient) by means of magnetic force microscopy at 5.2 K. The epitaxially grown films show a stress induced out-of-plane anisotropy. All samples exhibit a maze type domain structure at zero field. Domain size and contrast depend on film thickness. The effect of oxygen content could not clearly been determined. Field-dependent measurements were performed by ramping a perpendicular magnetic field of up to 800 mT continuously during imaging. Domain nucleation and growth takes place by discrete reorientation of regions, which have diameters similar to the final domain width.
Design, Synthesis, and Biological Activities of Closantel Analogues: Structural Promiscuity and Its Impact on Onchocerca volvulus (2011)

Onchocerciasis, or river blindness, is a neglected tropical disease that affects more than 37 million people worldwide, primarily in Africa and Central and South America. We have disclosed evidence that the larval-stage-specific chitinase, OvCHT1, may be a potential biological target for affecting nematode development. On the basis of screening efforts, closantel, a known anthelmintic drug, was discovered as a potent and highly specific OvCHT1 inhibitor. Originally, closantel's anthelmintic mode of action was believed to rely solely on its role as a proton ionophore; thus, the impact of each of its biological activities on O. volvulus L3 molting was investigated. Structure-activity relationship studies on an active closantel fragment are detailed, and remarkably, by use of a simple salicylanilide scaffold, compounds acting only as protonophores or chitinase inhibitors were identified. From these data, unexpected synergistic protonophore and chitinase inhibition activities have also been found to be critical for molting in O. volvulus L3 larvae.
Photovoltaic Hot-Spot Detection for Solar Panel Substrings Using AC Parameter Characterization (2015)

Hot spotting is a problem in photovoltaic (PV) systems that reduces panel power performance and accelerates cell degradation. In present day systems, bypass diodes are used to mitigate hot spotting, but it does not prevent hot spotting or the damage it causes. This paper presents an active hot-spot detection method to detect hot spotting within a series of PV cells, using ac parameter characterization. A PV cell is comprised of series and parallel resistances and parallel capacitance, which are affected by voltage bias, illumination, and temperature. Experimental results have shown that when a PV string is under a maximum power point tracking control, hot spotting in a single cell results in a capacitance increase and dc impedance increase. The capacitance change is detectable by measuring the ac impedance magnitude in the 10-70 kHz frequency range. An impedance value change due to hot spotting can be detected by monitoring one high-frequency measurement in the capacitive region and one low-frequency measurement in the dc impedance region. Alternatively, the dc impedance can also be calculated using dc operating point measurements. The proposed hot-spot detection method can be integrated into a dc-dc power converter that operates at the panel or subpanel level.
Mutation of histone H3 serine 86 disrupts GATA factor Ams2 expression and precise chromosome segregation in fission yeast (2015)

Abstract Eukaryotic genomes are packed into discrete units, referred to as nucleosomes, by organizing around scaffolding histone proteins. The interplay between these histones and the DNA can dynamically regulate the function of the chromosomal domain. Here, we interrogated the function of a pair of juxtaposing serine residues (S86 and S87) that reside within the histone fold of histone H3. We show that fission yeast cells expressing a mutant histone H3 disrupted at S86 and S87 ( hht2-S86AS87A ) exhibited unequal chromosome segregation, disrupted transcriptional silencing of centromeric chromatin and reduced expression of Ams2, a GATA-factor that regulates localization of the centromere-specific histone H3 variant CENP-A. We found that overexpression of ams2 + could suppress the chromosome missegregation phenotype that arose in the hht2-S86AS87A mutant. We further demonstrate that centromeric localization of SpCENP-A cnp1-1 was significantly compromised in hht2-S86AS87A , suggesting synergism between histone H3 and the centromere-targeting domain of SpCENP-A. Taken together, our work presents evidence for an uncharacterized serine residue in fission yeast histone H3 that affects centromeric integrity via regulating the expression of the SpCENP-A-localizing Ams2 protein. [173/200 words]
Nanoplumbers: biomaterials to fight cardiovascular diseases (2017)

The adequate management of cardiovascular diseases remains one of the major challenges of modern medicine. Nanomaterials may offer new and unique treatment opportunities that transcend the shortcomings of currently available therapies. Conventional administration of drugs is mainly based on the systemic delivery of therapeutic molecules, often leading to their non-specific distribution throughout the body, decreasing their efficacy and sometimes resulting in deleterious side effects. Through the precise control of the physicochemical properties of nanomaterials, such as size, drug loading and surface functionalization, nanoencapsulation of select therapeutic agents may enhance drug delivery and release at the sites of disease, ultimately increasing their effectiveness. Different biomaterials loaded with therapeutic drugs have been engineered for cardiovascular nanotherapy and evaluated in preclinical models. This review highlights how nanomedicines (i.e., nanoparticles and drugs) offer interesting perspectives in the treatment of atherosclerosis and heart ischemia, potentially affording new tools in the fight against cardiovascular diseases.
An Inverter-Based Hybrid ΔΣ Modulator (2008)

The SigmaDelta modulator presented in this paper exploits the advantages of new CMOS technologies by digitization on both architectural and circuit level. The target DR of the modulator is 77dB in 200kHz.
Medicinal plants of southern Africa. Part 2. Synthesis of 1,3-bis-(4-methoxyphenyl)penta-1,4-diene, a stereoisomer of dimethylhinokiresinol, and its 4-monomethoxy analogue (1988)

A six-step synthesis of the title compounds (6) and (7) from prop-2-yn-1-ol, and proceeding via 3-(4-methoxyphenyl)prop-1-yne, is described. Detailed 1H n.m.r. spectral analysis (500 MHz) suggests that the synthetic compounds have a 1,2-E stereochemistry in contrast to the Z-configuration present in the naturally occurring hinokiresinol (3). By utilizing a different, and much less efficient route, a small quantity of (Z)-3-(4-methoxyphenyl)-1-phenylpenta-1,4-diene (5) was obtained.
Pulsed laser second harmonic generation and thermal dephasing in periodically poled crystals (2005)

Computational study of nanosecond pulse laser radiation in periodically poled LiNbO<sub>3</sub> and LiTaO<sub>3</sub> crystals reveals the complex spacio-temporal evolution of the 1.064 &#956;m fundamental harmonic (FH) and second harmonic (SH) energy fields with associated temperature fields, leading to the thermal dephasing and inhibition of second harmonic generation (SHG). The investigated range of the laser input power is W<sub>0</sub>=0.5-50 W (with the pulse energy Q<sub>0</sub>=0.01-1 mJ/pulse and repetition rate of 50 kHz). For input laser powers W<sub>0</sub>>10 W the FH and SH energy fields are found to strongly couple with non-uniform temperature field leading to significant thermal dephasing and SHG efficiency loss. Heat generation and temperature distributions also exhibit very significant non-uniformities along and across the laser beam, maximizing at the rear or inside the crystal, depending on the input power. Performed study shows the feasibility of the effective thermal control with temperature gradient along the crystal allowing one to maintain (i) the irradiated zone within the temperature tolerance range and (ii) high SHG efficiency under high input laser powers.
Excited-state photophysics of donor-appended cobalt(II) porphyrins from picosecond transient absorption spectroscopy (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTExcited-state photophysics of donor-appended cobalt(II) porphyrins from picosecond transient absorption spectroscopyGlen R. Loppnow, Dan Melamed, A. Rachel Leheny, Andrew D. Hamilton, and Thomas G. SpiroCite this: J. Phys. Chem. 1993, 97, 35, 8969–8975Publication Date (Print):September 1, 1993Publication History Published online1 May 2002Published inissue 1 September 1993https://pubs.acs.org/doi/10.1021/j100137a022https://doi.org/10.1021/j100137a022research-articleACS PublicationsRequest reuse permissionsArticle Views363Altmetric-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 options Get e-Alerts