gebhart/patrepeval huggingface dataset:
Facile solvent extraction separation of Th-227 and Ac-225 based on room-temperature ionic liquids (2012)

Abstract New separation methodologies for radioisotopes are crucial to many medical applications. In this work, the solvent extraction of Th-227 and Ac-225 based on ionic liquids (ILs) was investigated using N , N , N´ , N´ -tetraoctyldiglycolamide (TODGA) or di(2-ethylhexyl)phosphoric acid (HDEHP) as an extractant. Four ILs, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C 4 mim][NTf 2 ]), 1-butyl-3-methylimidazolium bis(perfluoroethanesulfonyl)imide ([C 4 mim][BETI]), 1-butyl-2,3-trimethyleneimidazolium (trifluoromethanesulfonyl)imide ([BuI5][NTf 2 ]), and 1-benzyl pyridinium bis(trifluoromethanesulfonyl)imide ([PhCH 2 Py][NTf 2 ]) with different cation or anion structural features were used as diluents for the separation of Th-227 and Ac-225. Excellent extraction efficiencies and selectivities were found for Th-227/Ac-225 when HDEHP was used as an extractant in these ILs. The effects of different extractant concentrations in ILs and different aqueous phase acidities on extraction efficiencies and selectivities of Th-227/Ac-225 are also presented. The success in separation of Th-227 and Ac-225 isotopes highlights great potentials of use of ionic liquids in isotope production.
An mRNA Surveillance Mechanism That Eliminates Transcripts Lacking Termination Codons (2002)

Translation is an important mechanism to monitor the quality of messenger RNAs (mRNAs), as exemplified by the translation-dependent recognition and degradation of transcripts harboring premature termination codons (PTCs) by the nonsense-mediated mRNA decay (NMD) pathway. We demonstrate in yeast that mRNAs lacking all termination codons are as labile as nonsense transcripts. Decay of "nonstop" transcripts in yeast requires translation but is mechanistically distinguished from NMD and the major mRNA turnover pathway that requires deadenylation, decapping, and 5'-to-3' exonucleolytic decay. These data suggest that nonstop decay is initiated when the ribosome reaches the 3' terminus of the message. We demonstrate multiple physiologic sources of nonstop transcripts and conservation of their accelerated decay in mammalian cells. This process regulates the stability and expression of mRNAs that fail to signal translational termination.
Self-Aligned Technology for N-Polar GaN/Al(Ga)N MIS-HEMTs (2010)

In this letter, we introduce a scalable self-aligned technology for N-polar GaN MIS-HEMTs which can be used to achieve significant improvement in device performance by minimizing the source and drain access resistances. The methodology consists of a refractory-metal gate-first process followed by the regrowth of polarization-doped graded InGaN and InN layers by plasma-assisted molecular-beam epitaxy. The regrowth has been optimized to achieve ohmic contact resistance as low as 23 Ω-μm to the N-face 2-D electron gas. Excellent maximum current of 1.4 A/mm and a very low on resistance of 590 Ω-μm was achieved at (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> - V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> ) = 6 V for L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> = 500 nm. Peak transconductance of 343 mS/mm is also state of the art for the given gate length and aspect ratio. Excellent f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> .L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> product of 15.9 GHz-μm with minimal drain delay was also achieved for L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> = 600 nm.
Processing comparable corpora with Bilingual Suffix Trees (2002)

We introduce Bilingual Suffix Trees (BST), a data structure that is suitable for exploiting comparable corpora. We discuss algorithms that use BSTs in order to create parallel corpora and learn translations of unseen words from comparable corpora. Starting with a small bilingual dictionary that was derived automatically from a corpus of 5.000 parallel sentences, we have automatically extracted a corpus of 33.926 parallel phrases of size greater than 3, and learned 9 new word translations from a comparable corpus of 1.3M words (100.000 sentences).
Synthetic Array Heterodyne Detection: Developments Within the Caliope CO2 Dial Program (1995)

A new technique, Synthetic Array Heterodyne Detection, offers a wider field of view and improved signal to noise for coherent DIAL systems by reducing speckle interference. We have implemented a synthetic multi pixel array using a CO 2 laser on a single element HgCdTe photodiode.
Expression of Cytosolic and Plastid Acetyl-Coenzyme A Carboxylase Genes in Young Wheat Plants, (2003)

Expression of cytosolic and plastid acetyl-coenzyme A carboxylase (ACCase) gene families at the mRNA level was analyzed in developing wheat (Triticum aestivum) plants. The major plastid ACCase mRNA level is high in the middle part of the plant and low in roots and leaf blades. An alternative plastid ACCase transcript initiated at a different promoter and using an alternative 5' splice site for the first intron accumulates to its highest level in roots. Cytosolic ACCase mRNA also consists of two species, one of which is present at approximately a constant level, whereas the other accumulates to a high level in the lower sheath section. It is likely that different promoters are also responsible for the two forms of cytosolic ACCase mRNA. The abundances of cytosolic and plastid ACCase mRNAs in the sheath section of the plant are similar. ACCase protein level is significantly lower in the leaf blades, in parallel with changes in the total ACCase mRNA level. Homoeologous ACCase genes show the same expression patterns and similar mRNA levels, suggesting that none of the genes was silenced or acquired new tissue specificity after polyploidization.
The Synthesis of Haptens and Their Use for the Development of Monoclonal Antibodies for Treating Methamphetamine Abuse (2009)

In addition to addiction, the repeated use of (+)-methamphetamine [(+)-METH], (+)-amphetamine [(+)-AMP], or (+/-)-3,4-methylenedioxymethamphetamine ((+/-)-MDMA, commonly called ecstasy) can lead to life-threatening medical problems including cardiovascular injury, severe depression, and psychosis. Currently, there are no specific pharmacotherapies to treat these medical problems. In this study, we report the design and synthesis of two haptens, (S)-(+)-3-(9-carboxynonyloxy)methamphetamine (3a, (+)-METH MO10) and (S)-(+)-3-(5-carboxypentyloxy)methamphetamine (3b, (+)-METH MO6), and their use in generating high affinity (low K(D) value) monoclonal antibodies (mAbs) against (+)-METH, (+)-AMP, and/or (+)-MDMA. On the basis of results from the determination of mAb K(D) values and ligand specificity, the mAbs generated from hapten 3a showed the greatest promise for generating active and passive immunotherapies for treating overdose or addiction from (+)-METH-like stimulants.
Flexible Distributed Pressure Sensing Strip for a Urethral Catheter (2015)

A multi-sensor flexible strip is developed for a urethral catheter to measure distributed pressure in a human urethra. The developed sensor strip has important clinical applications in urodynamic testing for analyzing the causes of urinary incontinence in patients. There are two major challenges in the development of the sensor. First, a highly sensitive sensor strip that is flexible enough for urethral insertion into a human body is required and second, the sensor has to work reliably in a liquid in-vivo environment in the human body. Capacitive force sensors are designed and micro-fabricated using polyimide/PDMS substrates and copper electrodes. To remove the parasitic influence of urethral tissues which create fringe capacitance that can lead to significant errors, a reference fringe capacitance measurement sensor is incorporated on the strip. The sensing strip is embedded on a catheter and experimental in-vitro evaluation is presented using a bench-top pressure chamber. The sensors on the strip are able to provide the required sensitivity and range. Preliminary experimental results also show promise that by using measurements from the reference parasitic sensor on the strip, the influence of parasitics from human tissue on the pressure measurements can be removed.
Simultaneous Deletion of the<i>9GL</i>and<i>UK</i>Genes from the African Swine Fever Virus Georgia 2007 Isolate Offers Increased Safety and Protection against Homologous Challenge (2016)

Currently, there is no commercially available vaccine against African swine fever. Outbreaks of the disease are devastating to the swine industry and are caused by circulating strains of African swine fever virus. Here, we report a putative vaccine derived from a currently circulating strain but containing two deletions in two separate areas of the virus, allowing increased safety. Using this genetically modified virus, we were able to vaccinate swine and protect them from developing ASF. We were able to achieve protection from disease as early as 2 weeks after vaccination, even when the pigs were exposed to a higher than normal concentration of ASFV.
Designing durable icephobic surfaces (2016)

Ice accretion has a negative impact on critical infrastructure, as well as a range of commercial and residential activities. Icephobic surfaces are defined by an ice adhesion strength τice < 100 kPa. However, the passive removal of ice requires much lower values of τice, such as on airplane wings or power lines (τice < 20 kPa). Such low τice values are scarcely reported, and robust coatings that maintain these low values have not been reported previously. We show that, irrespective of material chemistry, by tailoring the cross-link density of different elastomeric coatings and by enabling interfacial slippage, it is possible to systematically design coatings with extremely low ice adhesion (τice < 0.2 kPa). These newfound mechanisms allow for the rational design of icephobic coatings with virtually any desired ice adhesion strength. By using these mechanisms, we fabricate extremely durable coatings that maintain τice < 10 kPa after severe mechanical abrasion, acid/base exposure, 100 icing/deicing cycles, thermal cycling, accelerated corrosion, and exposure to Michigan wintery conditions over several months.
Specificity of <i>Streptomyces griseus</i> aminopeptidase and modulation of activity by divalent metal ion binding and substitution (1993)

Streptomyces griseus aminopeptidase is a calcium-activated zinc metalloenzyme characterized by a high enzymic reactivity, high thermal stability and low molecular mass [Spungin, A. and Blumberg, S. (1989) Eur. J. Biochem. 183, 471-477]. A study of the specificity of S. griseus aminopeptidase using amino acid 4-nitroanilide substrates shows that the leucine derivative is the best substrate. Derivatives of other hydrophobic amino acids, methionine and phenylalanine, are also excellent substrates for the enzyme. The 4-nitroanilides of alanine, valine, proline and lysine are good substrates whereas those of the small size glycine and the acidic amino acids are very poor. No hydrolysis of a terminal Xaa residue can be detected with Xaa-proline N-terminal sequences. Calcium ions bind to the enzyme and modulate its activity in a substrate-dependent manner. The catalytically essential zinc of S. griseus aminopeptidase is removed by dialysis against 1,10-phenanthroline and replaced by manganese or cobalt ions, resulting in enzyme derivatives of altered specificities. Thus, whereas the zinc enzyme hydrolyzes leucine 4-nitroanilide at a 10-fold faster rate than the manganese or cobalt enzymes, the cobalt enzyme hydrolyzes alanine 4-nitroanilide at a more than 20-fold faster rate than the zinc or manganese enzymes.
Graphene quantum dot bolometer camera: practical approaches and preliminary results (2023)

Graphene is an exciting candidate for the detection of high-frequency electromagnetic radiation. Here, we have studied the bolometric performance of epitaxial graphene quantum dots (Q.D.s) on the silicon carbide (SiC) substrate in the terahertz (THz) range. The graphene Q.D. having a diameter in the 200 nm range, exhibited an extremely high resistance variation with temperature up to 4.7 MΩ K-1, a crucial parameter for the hot electron bolometers. The graphene Q.D.s bolometers have been fabricated in different geometrical configurations, such as variations in electrode spacing (2.5 and 5.0 μm) and parallelly connected arrays of 4 and 8 Q.D.s. It is demonstrated that the absorbed power can be improved by tuning the bolometer geometrical configuration and the active graphene area, and the electrical responsivity is still very high for an extensive range of absorbed power. Additionally, we report that the photo response of graphene Q.D. bolometer devices is meagerly affected by the presence of a magnetic field as high as 15 T. The results presented here open ways to continue to optimize and realize the chip-scale matrix of the graphene Q.D.s bolometers for THz imaging and magneto-optical spectroscopy applications.
Mutations Affecting Tea Blockade and Ion Permeation in Voltage-activated K <sup>+</sup> Channels (1990)

Voltage-dependent ion channels are responsible for electrical signaling in neurons and other cells. The main classes of voltage-dependent channels (sodium-, calcium-, and potassium-selective channels) have closely related molecular structures. For one member of this superfamily, the transiently voltage-activated Shaker H4 potassium channel, specific amino acid residues have now been identified that affect channel blockade by the small ion tetraethylammonium, as well as the conduction of ions through the pore. Furthermore, variation at one of these amino acid positions among naturally occurring potassium channels may account for most of their differences in sensitivity to tetraethylammonium.
SAR image formation uncorrupted by multiple-bounce artifacts (2003)

This analysis develops an innovative image reconstruction technique for synthetic aperture radar (SAR) based upon the removal of multiple-bounce (MB) artifacts. The basic concept is that the phase history measurements include the realistic effects of MB interactions. These measured phase history data are decomposed into contributions due to the desired single-bounce (SB) scattering events and the undesirable MB interactions. An enhanced quality image can be constructed by retaining only the SB contributions.
IgY antibodies for the immunoprophylaxis and therapy of respiratory infections (2018)

Emergence of drug resistance among the causative organisms for respiratory tract infections represents a critical challenge to the global health care community. Further, although vaccination can prevent disease, vaccine development is impeded by several factors. Therefore, novel approaches to treat and manage respiratory infections are urgently needed. Passive immunization represents a possible alternative to meet this need. Immunoglobulin Y antibodies (IgYs) from the yolk of chicken eggs have previously been used against bacterial and viral infections in human and animals. Their advantages include lack of reaction with mammalian Fc receptors, low production cost, and ease of extraction. Compared to mammalian IgGs, they have higher target specificity and greater binding avidity. They also possess remarkable pathogen-neutralizing activity in the respiratory tract and lungs. In this review, we provide an overview of avian IgYs and describe their potential therapeutic applications for the prevention and treatment of respiratory infections.
Phase Contrast Microscopy with Digital Holography (1998)

We present a new application of digital holography for phase contrast microscopy. This new holographic imaging technique uses a CCD camera as recording device and a numerical method for the hologram reconstruction. Preliminary results with a biological sample are presented.
Sensitivity study of an ultrasound coupled transrectal electrical impedance tomography system for prostate imaging (2010)

In 2009, prostate cancer ranked as the most common cancer and the second most fatal cancer in men in the United States. Unfortunately, the current clinical diagnostic methods (e.g. prostate-specific antigen (PSA), digital rectal examination, endorectal MRI, transrectal ultrasound, biopsy) used for detecting and staging prostate cancer are limited. It has been shown that cancerous prostate tissue has significantly different electrical properties when compared to benign tissues. Based on these electrical property findings, a transrectal electrical impedance tomography (TREIT) system is proposed as a novel prostate imaging modality. The TREIT system comprises an array of electrodes interfaced with a clinical transrectal ultrasound (TRUS) probe. We evaluate this imaging system through a series of phantom imaging experiments to assess the system's ability to image high and low contrast objects at various positions. We found that the TREIT system can easily discern high contrast inclusions of 1 cm in diameter at distances centered at two times the radius of the TREIT probe away from the probe surface. Furthermore, this technology's ability to detect low contrast inclusions suggests that it has the potential to successfully detect prostate cancer.
Triggered Attention for End-to-end Speech Recognition (2019)

A new system architecture for end-to-end automatic speech recognition (ASR) is proposed that combines the alignment capabilities of the connectionist temporal classification (CTC) approach and the modeling strength of the attention mechanism. The proposed system architecture, named triggered attention (TA), uses a CTC-based classifier to control the activation of an attention-based decoder neural network. This allows for a frame-synchronous decoding scheme with an adjustable look-ahead parameter to control the induced delay and opens the door to streaming recognition with attention-based end-to-end ASR systems. We present ASR results of the TA model on three data sets of different size and language and compare the scores to a well-tuned attention-based end-to-end ASR baseline system, which consumes input frames in the traditional full-sequence manner. The proposed triggered attention (TA) decoder concept achieves similar or better ASR results in all experiments compared to the full-sequence attention model, while also limiting the decoding delay to two look-ahead frames, which in our setup corresponds to an output delay of 80 ms.
Three-Dimensional Tissue Assemblies: Novel Models for the Study of<i>Salmonella enterica</i>Serovar Typhimurium Pathogenesis (2001)

The lack of readily available experimental systems has limited knowledge pertaining to the development of Salmonella-induced gastroenteritis and diarrheal disease in humans. We used a novel low-shear stress cell culture system developed at the National Aeronautics and Space Administration in conjunction with cultivation of three-dimensional (3-D) aggregates of human intestinal tissue to study the infectivity of Salmonella enterica serovar Typhimurium for human intestinal epithelium. Immunohistochemical characterization and microscopic analysis of 3-D aggregates of the human intestinal epithelial cell line Int-407 revealed that the 3-D cells more accurately modeled human in vivo differentiated tissues than did conventional monolayer cultures of the same cells. Results from infectivity studies showed that Salmonella established infection of the 3-D cells in a much different manner than that observed for monolayers. Following the same time course of infection with Salmonella, 3-D Int-407 cells displayed minimal loss of structural integrity compared to that of Int-407 monolayers. Furthermore, Salmonella exhibited significantly lower abilities to adhere to, invade, and induce apoptosis of 3-D Int-407 cells than it did for infected Int-407 monolayers. Analysis of cytokine expression profiles of 3-D Int-407 cells and monolayers following infection with Salmonella revealed significant differences in expression of interleukin 1alpha (IL-1alpha), IL-1beta, IL-6, IL-1Ra, and tumor necrosis factor alpha mRNAs between the two cultures. In addition, uninfected 3-D Int-407 cells constitutively expressed higher levels of transforming growth factor beta1 mRNA and prostaglandin E2 than did uninfected Int-407 monolayers. By more accurately modeling many aspects of human in vivo tissues, the 3-D intestinal cell model generated in this study offers a novel approach for studying microbial infectivity from the perspective of the host-pathogen interaction.
Metal-assisted and microwave-accelerated evaporative crystallization: an approach to rapid crystallization of biomolecules (2016)

Our laboratory has recently introduced and demonstrated the use of the metal-assisted and microwave-accelerated evaporative crystallization (MA-MAEC) technique for rapid crystallization of biomolecules (e.g., amino acids, peptides and proteins). The MA-MAEC technique utilizes metal nanoparticles (silver, gold, copper, nickel, iron oxide, indium tin oxide), which are deposited on to iCrystal plates or glass surfaces to serve as selective nucleation sites and microwave-transparent medium to generate microwave-induced temperature gradients. In this highlight article, we will chronicle the effectiveness of the MA-MAEC technique as a rapid, efficient and easy to use technique for crystallization of biomolecules in potential applications in the pharmaceutical industry.
Automated fiber pigtailing technology (2002)

The high cost of optoelectronic (OE) devices is due mainly to the labor-intensive packaging process. Manually pigtailing such devices as single-mode laser diodes and modulators is very time consuming with poor quality control. The Photonics Program and the Engineering Research Division at LLNL are addressing several issues associated with automatically packaging OE devices. A fully automated system must include high-precision fiber alignment, fiber attachment techniques, in-situ quality control, and parts handling and feeding. This paper will present on-going work at LLNL in the areas of automated fiber alignment and fiber attachment. For the fiber alignment, we are building an automated fiber pigtailing machine (AFPM) which combines computer vision and object recognition algorithms with active feedback to perform sub-micron alignments of single-mode fibers to modulators and laser diodes. We expect to perform sub-micron alignments in less than five minutes with this technology. For fiber attachment, we are building various geometries of silicon microbenches which include onboard heaters to solder metal-coated fibers and other components in place; these designs are completely compatible with an automated process of OE packaging.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>