gebhart/patrepeval huggingface dataset:
Role and expression of neurotrophins and the trk family of tyrosine kinase receptors in neural growth and rescue after injury. (1993)

Molecular cloning of genes for the neurotrophin family and the identification of their high-affinity receptors have recently contributed to our understanding of neurotrophic interactions in the vertebrate nervous system. From their primary sites of synthesis, novel neuronal populations that may be sensitive to the neurotrophins have been identified. Protective roles for these factors following epileptic, ischemic, and hypoglycemic insults have been inferred. Documented neurotrophic actions on basal forebrain cholinergic neurons and mesencephalic dopaminergic neurons imply future clinical applications for the treatment of dementia of both Alzheimer's and Parkinson's disease. Studies on structure-function relationships of the neurotrophins hold promises for the development of specific receptor agonists and antagonists with possible basic science and clinical applications.
Improved laser-beam uniformity using the angular dispersion of frequency-modulated light (1989)

A new technique is presented for obtaining highly smooth focused laser beams. This approach is consistent with the constraints on frequency tripling the light, and it will not produce any significant high-intensity spikes within the laser chain, making the technique attractive for the high-power glass lasers used in current fusion experiments. Smoothing is obtained by imposing a frequency-modulated bandwidth on the laser beam using an electro-optic crystal. A pair of gratings is used to disperse the frequencies across the beam, without distorting the temporal pulse shape. The beam is broken up into beamlets, using a phase plate, such that the beamlet diffraction-limited focal spot is the size of the target. The time-averaged interference between beamlets is greatly reduced because of the frequency differences between the beamlets, and the result is a relatively smooth diffraction-limited intensity pattern on target.
Breaking the Species Barrier: Derivation of Germline‐Competent Embryonic Stem Cells from Mus spretus × C57BL/6 Hybrids (2004)

Embryonic stem (ES) cells, which can differentiate into almost all types of cells, have been derived from the house mouse Mus musculus, rat, rabbit, humans, and other species. Transmission of the genotype to the offspring of chimeras has been achieved only with M. musculus ES cells, limiting targeted mutagenesis using ES cells to this species. Mus spretus, which exhibits many genetic polymorphisms with M. musculus, displays dominant resistance to cancer and inflammation, making derived inbred strains very useful in positional cloning and interspecies mapping. We show here for the first time the derivation of ES cells from hybrid blastocysts, obtained by the mating of two different species, namely Mus musculus and Mus spretus, and their use for the generation of chimeric mice that transmit the Mus spretus genotype and phenotype to the offspring. These hybrid ES cells allow the genetic manipulation of Mus spretus, as an alternative to Mus musculus.
The natural silk spinning process (2001)

The spinning mechanism of natural silk has been an open issue. In this study, both the conformation transition from random coil to beta sheet and the beta sheet aggregation growth of silk fibroin are identified in the B. mori regenerated silk fibroin aqueous solution by circular dichroism (CD) spectroscopy. A nucleation-dependent aggregation mechanism, similar to that found in prion protein, amyloid beta (Abeta) protein, and alpha-synuclein protein with the conformation transition from a soluble protein to a neurotoxic, insoluble beta sheet containing aggregate, is a novel suggestion for the silk spinning process. We present evidence that two steps are involved in this mechanism: (a) nucleation, a rate-limiting step involving the conversion of the soluble random coil to insoluble beta sheet and subsequently a series of thermodynamically unfavorable association of beta sheet unit, i.e. the formation of a nucleus or seed; (b) once the nucleus forms, further growth of the beta sheet unit becomes thermodynamically favorable, resulting a rapid extension of beta sheet aggregation. The aggregation growth follows a first order kinetic process with respect to the random coil fibroin concentration. The increase of temperature accelerates the beta sheet aggregation growth if the beta sheet seed is introduced into the random coil fibroin solution. This work enhances our understanding of the natural silk spinning process in vivo.
Exploring the limits of pre-amorphization implants on controlling channeling and diffusion of low energy B implants and ultra shallow junction formation (2003)

Reducing channeling of B implants and transient enhanced diffusion (TED) is very critical for the formation of ultra shallow junctions required for deep sub-micron devices. As the ion energy required for junction formation is reduced (<5 keV) due to device shrinking, the use of high tilt angle (typically 7-10 deg) becomes ineffective in suppressing channeling. The formation of a thin amorphous layer close to the surface prior to B implant has shown to be very efficient in eliminating channeling. Such layers can be formed using a Ge/sup +/ implant, and the thickness of the amorphous layers can be varied with Ge/sup +/ ion energy and dose. In addition if optimized, Ge/sup +/ pre-amorphization implants (PAI) can also minimize the TED of B by reducing the concentration of point defects generated by B implants. However, a Ge PAI itself introduces point defects and can result in TED with sub keV B implants. This paper explores the limits and optimized conditions of Ge PAI prior to low energy B implants (=1 keV) for the formation of junctions for deep sub-quarter micron devices.
Pressure tolerant single-mode fiber coupler (1987)

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text C. A. Villarruel, M. Abebe, A. Dandridge, A. S. Greenblatt, and L. Schuette, "Pressure tolerant single-mode fiber coupler," Appl. Opt. 26, 1824-1826 (1987) Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article
Fabrication of metallic patterns by microstencil lithography on polymer surfaces suitable as microelectrodes in integrated microfluidic systems (2006)

Microstencil lithography, i.e. local deposition of micrometer scale patterns through small shadow masks, is a promising method for metal micropattern definition on polymer substrates that cannot be structured using organic-solvent-based photoresist technology. We propose to apply microstencil lithography to fabricate microelectrodes on flat and 3D polymer substrates, such as PMMA or SU-8, which form parts of microfluidic systems with integrated microelectrodes. Microstencil lithography is accompanied by two main issues when considered for application as a low-cost, reproducible alternative to standard photolithography on polymer substrates. In this paper we assess in detail (i) the reduction of aperture size (clogging) after several metal evaporation steps and corresponding change of deposited pattern size and (ii) loss in the resolution (blurring) of the deposited microstructures when there is a several micrometers large gap between the stencil membrane and the substrate. The clogging of stencil apertures induced by titanium and copper evaporation was checked after each evaporation step, and it was determined that approximately 50% of the thickness of the evaporated metals was deposited on the side walls of the stencil apertures. The influence of a gap on the deposited structures was analyzed by using 18 m thick SU-8 spacers placed between the microstencil and the substrate. The presence of an 18 m gap made the deposited structures notably blurred. The blurring mechanism of deposited structures is discussed based on a simplified geometrical model. The results obtained in this paper allow assessing the feasibility of using stencil-based lithography for unconventional surface patterning, which shows the limits of the proposed method, but also provides a guideline on a possible implementation for combined polymer-electrode microsystems, where standard photoresist technology fails.
A New Tool for Studying the in Situ Growth Processes for Self-Assembled Monolayers under Ambient Conditions (1999)

A new tool for studying self-assembled monolayer (SAM) nucleation and growth processes on faceted inorganic substrates under ambient conditions is reported herein. The methodology involves coating an atomic force microscope tip with molecules of interest and raster scanning across a substrate of interest with the modified tip. Large scale images of the deposition process provide kinetic information about the nucleation and growth of SAMs. The water meniscus, which is the transport medium in these experiments, is proposed to strongly influence the growth process for 1-octadecanethiol and 16-mercaptohexadecanoic acid. The former involves an island formation and subsequent growth behavior while the latter shows evidence of more random growth. Lattice-resolved images of both SAM structures have been obtained at the end of film growth, and in the case of the 1-octadecanethiol SAM, lattice-resolved images were obtained for the SAM islands. The virtues of this novel technique are its simplicity, adsorbate generality, and serial nature, which allows one to control monolayer growth in a step-by-step process with concomitant imaging capabilities.
Cytochrome P450 metabolizing fatty acids in plants: characterization and physiological roles (2010)

In plants, fatty acids (FA) are subjected to various types of oxygenation reactions. Products include hydroxyacids, as well as hydroperoxides, epoxides, aldehydes, ketones and α,ω-diacids. Many of these reactions are catalysed by cytochrome P450s (P450s), which represent one of the largest superfamilies of proteins in plants. The existence of P450-type metabolizing FA enzymes in plants was established approximately four decades ago in studies on the biosynthesis of lipid polyesters. Biochemical investigations have highlighted two major characteristics of P450s acting on FAs: (a) they can be inhibited by FA analogues carrying an acetylenic function, and (b) they can be enhanced by biotic and abiotic stress at the transcriptional level. Based on these properties, P450s capable of producing oxidized FA have been identified and characterized from various plant species. Until recently, the vast majority of characterized P450s acting on FAs belonged to the CYP86 and CYP94 families. In the past five years, rapid progress in the characterization of mutants in the model plant Arabidopsis thaliana has allowed the identification of such enzymes in many other P450 families (i.e. CYP703, CYP704, CYP709, CYP77, CYP74). The presence in a single species of distinct enzymes characterized by their own regulation and catalytic properties raised the question of their physiological meaning. Functional studies in A. thaliana have demonstrated the involvement of FA hydroxylases in the synthesis of the protective biopolymers cutin, suberin and sporopollenin. In addition, several lines of evidence discussed in this minireview are consistent with P450s metabolizing FAs in many aspects of plant biology, such as defence against pathogens and herbivores, development, catabolism or reproduction.
Use of xantham gum to suspend large particles during flow cytometric analysis and sorting (1989)

In this report we describe the use of xantham gum as a biologically inert material for increasing the viscosity of a suspension of cells or particles during flow cytometric analysis and sorting. A 0.1% concentration of xantham gum in culture medium or saline will increase the viscosity approximately 9-fold. For suspensions of multicellular spheroids 100-400 microns in diameter the measured sedimentation velocity was approximately 9 times slower than that in medium alone. Thus, spheroids of 100 microns diameter remain in suspension in 0.1% xantham gum for 66 min, compared to 7.5 min in culture medium. This allows extended periods of sorting without stirring or agitating the sample suspension. The xantham gum solution is noncytotoxic for periods up to 8 h as measured by clonogenicity assay. Xantham gum has the added advantage that the viscosity is significantly reduced when the solution is subjected to shear stress, such as during flow. This technique should be applicable to extended sorting of suspensions of spheroids, plant cells, and other large particles, as well as for analyzing and sorting single cells for extended periods.
Cigarette smoke induces endoplasmic reticulum stress and the unfolded protein response in normal and malignant human lung cells (2008)

These data indicate that chronic ER stress and recruitment of one or more UPR effector arms upon exposure to CS may play a pivotal role in the etiology or progression of lung cancers, and that phospho-eIF2 alpha and BiP may have diagnostic and/or therapeutic potential. Furthermore, we speculate that upregulation of UPR regulators (in particular BiP) may provide a pro-survival advantage by increasing resistance to cytotoxic stresses such as hypoxia and chemotherapeutic drugs, and that UPR induction is a potential mechanism that could be attenuated or reversed resulting in a more efficacious treatment strategy for lung cancer.
Bacterial display in combinatorial protein engineering (2011)

Technologies for display of recombinant protein libraries are today essential tools in many research-intensive fields, such as in the drug discovery processes of biopharmaceutical development. Phage display is still the most widely used method, but alternative systems are available and are becoming increasingly popular. The most rapidly expanding of the alternative systems are the cell display-based technologies, offering innovative strategies for selection and characterization of affinity proteins. Most investigations have focused on eukaryotic yeast for display of protein libraries, but similar systems are also being developed using prokaryotic hosts. This review summarizes the field of bacterial surface display with a strong emphasis on library applications for generation of new affinity proteins. The main focus will be on the most recent progress of the work on primarily Escherichia coli, but also on studies using a recently developed system for display on Gram-positive Staphylococcus carnosus. In addition, general strategies for combinatorial protein engineering using cell display are discussed along with the latest developments of new methodologies with comparisons to mainly phage display technology.
Integral Pressure Restrictor for Capillary SFC (1986)

Journal Article Integral Pressure Restrictor for Capillary SFC Get access E.J. Guthrie, E.J. Guthrie J&W Scientific, Inc., 91 Blue Ravine Road, Folsom, California 95630 Search for other works by this author on: Oxford Academic PubMed Google Scholar H.E. Schwartz H.E. Schwartz Brownlee Labs, Inc., 2045 Martin Avenue, Santa Clara, California 95050 Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Chromatographic Science, Volume 24, Issue 6, June 1986, Pages 236–241, https://doi.org/10.1093/chromsci/24.6.236 Published: 01 June 1986 Article history Received: 25 April 1986 Published: 01 June 1986
Loss is its own Reward: Self-Supervision for Reinforcement Learning (2016)

Reinforcement learning optimizes policies for expected cumulative reward. Need the supervision be so narrow? Reward is delayed and sparse for many tasks, making it a difficult and impoverished signal for end-to-end optimization. To augment reward, we consider a range of self-supervised tasks that incorporate states, actions, and successors to provide auxiliary losses. These losses offer ubiquitous and instantaneous supervision for representation learning even in the absence of reward. While current results show that learning from reward alone is feasible, pure reinforcement learning methods are constrained by computational and data efficiency issues that can be remedied by auxiliary losses. Self-supervised pre-training and joint optimization improve the data efficiency and policy returns of end-to-end reinforcement learning.
Regulation of fatty acid metabolism in bacteria (2007)

In Escherichia coli, the main player in transcription regulation of fatty acid metabolism is the FadR protein, which is involved in negative regulation of fatty acid degradation and in positive and negative regulation of the cellular processes related to it, as well as in positive regulation of the biosynthesis of unsaturated fatty acids in a concerted manner with negative regulation of FabR. On the other hand, Bacillus subtilis possesses two global transcriptional regulators, FadR (YsiA) and FapR. B. subtilis FadR represses fatty acid degradation, whereas FapR represses almost all the processes in the biosynthesis of saturated fatty acids and phospholipids. Furthermore, Streptococcus pneumoniae FabT represses the genes of fatty acid biosynthesis that are clustered in its genome. Long-chain acyl-CoAs appear to be metabolic signals for fatty acid degradation by bacteria in general, and antagonize the FadR protein from either E. coli or B. subtilis. However, malonyl-CoA is a metabolic signal for fatty acid and phospholipid biosynthesis by Gram-positive low-GC bacteria, and it antagonizes FapR. These would be the primary aspects for understanding the elaborate and complex regulation of fatty acid metabolism in bacteria to maintain membrane lipid homeostasis.
Some Multi-Contract Decision-Theoretic Competitive Bidding Models (1971)

This paper reviews the principal public literature concerned with expected-profit decision-theoretic closed-competitive-bidding models. It makes extensions of previous formulations for static multi-contract bidding situations with and without cost dependencies and resource constraints. The same decision model is reformulated to utilize numerical, Lagrange-multiplier, dynamic, and integer linear programming techniques according to the information available to the bidder. A zero-one integer programming formulation is well suited to utilize subjective probabilities of winning estimates. Finally, the paper suggests a format for further development.
Cerebral Oxygenation during Hemorrhagic Shock: Perils of Hyperventilation and the Therapeutic Potential of Hypoventilation (2000)

During hemorrhage, alterations in ventilation significantly changed PbrO2: hyperventilation increased brain-tissue hypoxia whereas hypoventilation alleviated it. This finding suggests that hyperventilation has deleterious effects on brain oxygenation in patients with hemorrhagic shock and those with head trauma. Conversely, hypoventilation with resultant hypercapnia may actually help resolve hemorrhagic shock-induced cerebral hypoxia.
Association Study of Trauma Load andSLC6A4Promoter Polymorphism in Posttraumatic Stress Disorder (2010)

We find evidence for a gene-environment interplay for PTSD and show that genetic influences lose importance when environmental factors cause an extremely high trauma burden to an individual. In the future, it may be important to determine whether the effectiveness of therapeutic interventions in PTSD is also modulated by the SLC6A4 genotype.
Reduction of polygalacturonase activity in tomato fruit by antisense RNA (1988)

Polygalacturonase [PG; poly(1,4-alpha-D-galacturonide) glycanhydrolase; EC 3.2.1.15] is expressed in tomato only during the ripening stage of fruit development. PG becomes abundant during ripening and has a major role in cell wall degradation and fruit softening. Tomato plants were transformed to produce antisense RNA from a gene construct containing the cauliflower mosaic virus 35S promoter and a full-length PG cDNA in reverse orientation. The construct was integrated into the tomato genome by Agrobacterium-mediated transformation. The constitutive synthesis of PG antisense RNA in transgenic plants resulted in a substantial reduction in the levels of PG mRNA and enzymatic activity in ripening fruit. The steady-state levels of PG antisense RNA in green fruit of transgenic plants were lower than the levels of PG mRNA normally attained during ripening. However, analysis of transcription in isolated nuclei demonstrated that the antisense RNA construct was transcribed at a higher rate than the tomato PG gene(s). Analysis of fruit from transgenic plants demonstrated a reduction in PG mRNA and enzymatic activity of 70-90%. The reduction in PG activity did not prevent the accumulation of the red pigment lycopene.
An IL-1 inhibitor from human monocytes. Production and characterization of biologic properties. (1989)

Previous studies have described a 22 kD IL-1 inhibitor in the supernatant of human monocytes cultured on adherent immune complexes (J. Immunol. 134:3868, 1985). The studies reported herein further detail the conditions of production and biological properties of this IL-1 inhibitor. The inhibitor was produced by human monocytes cultured on adherent human IgG with maximal production between 8 and 24 hr. The IL-1 inhibitor was not performed in the cells but required transcription and new protein synthesis. The inhibitor blocked IL-1 augmentation of PHA-induced murine thymocyte proliferation but not IL-2-induced stimulation of CTLL or HT-2 cell lines. In addition, the inhibitor blocked IL-1-stimulated collagenase production from rabbit articular chondrocytes and IL-1-induced PGE2 production from human fibroblasts and synovial cells. The IL-1 inhibitor was not transforming growth factor beta (TGF beta) as determined by: the failure of anti-TGF beta antibodies to reduce IL-1 inhibitory activity, the separation of TGF beta from the IL-1 inhibitor by ion exchange chromatography, and the failure of TGF beta to inhibit IL-1-induced PGE2 production from synovial cells. IL-1 and the inhibitor showed no immunological cross-reactivity by Western blot analysis. The inhibitor specifically blocked binding of IL-1 to its receptor on the murine thymoma cell line EL4-6.1. These results indicate that a specific inhibitor of IL-1-induced immune and inflammatory cell responses is produced by monocytes cultured on adherent immune complexes or adherent IgG. This IL-1 inhibitor may be of importance in modulating the effects of IL-1 in the monocyte microenvironment.
Evaluation of Virucidal Compounds for Inactivation of Rhinovirus on Hands (1978)

Antimicrobial liquids and foams were applied to the hands to determine their virucidal activity against rhinoviruses. Dilute solutions (1%) of iodine in ethyl alcohol or in water were most effective in causing inactivation of rhinovirus when applied immediately after viral contamination. Iodine also had a residual virucidal activity which persisted on the hands for up to 1 h. Less effective inactivation of rhinovirus was observed with foams containing 0.23% hexachlorophene and 58% ethyl alcohol and another containing 0.2% benzalkonium chloride and 50% ethyl alcohol. Ethyl alcohol alone or in a mixture with benzyl alcohol was the least effective preparation tested.