gebhart/patrepeval huggingface dataset:
Two Distinct Transmembrane Serine/Threonine Kinases from <i>Drosophila melanogaster</i> Form an Activin Receptor Complex (1994)

A transmembrane protein serine/threonine kinase, Atr-I, that is structurally related to receptors for members of the transforming growth factor-beta (TGF-beta) family has been cloned from Drosophila melanogaster. The spacing of extracellular cysteines and the cytoplasmic domain of Atr-I resemble most closely those of the recently described mammalian type I receptors for TGF-beta and activin. When expressed alone in test cells, Atr-I is unable to bind TGF-beta, activin, or bone morphogenetic protein 2. However, Atr-I binds activin efficiently when coexpressed with the distantly related Drosophila activin receptor Atr-II, with which it forms a heteromeric complex. Atr-I can also bind activin in concert with mammalian activin type II receptors. Two alternative forms of Atr-I have been identified that differ in an ectodomain region encompassing the cysteine box motif characteristic of receptors in this family. Comparison of Atr-I with other type I receptors reveals the presence of a characteristic 30-amino-acid domain immediately upstream of the kinase region in all these receptors. This domain, of unknown function, contains a repeated Gly-Ser sequence and is therefore referred to as the GS domain. Maternal Atr-I transcripts are abundant in the oocyte and widespread during embryo development and in the imaginal discs of the larva. The structural properties, binding specificity, and dependence on type II receptors define Atr-I as an activin type I receptor from D. melanogaster. These results indicate that the heteromeric kinase structure is a general feature of this receptor family.
Generation of a 40-GHz pulse stream by pulse multiplication with a sampled fiber Bragg grating (2000)

A sinc-sampled fiber Bragg grating is used to achieve multiplication of the repetition rate of a pulse stream from 10 to 40 GHz. The spectral characteristics of the grating ensure that the resultant pulses-solitons of 3.4-ps width-have the same individual pulse characteristics as those of the input.
A Phospholipid Derivative of Cytosine Arabinoside and Its Conversion to Phosphatidylinositol by Animal Tissue (1977)

We have synthesized an analog (ara-CDP-DL-dipalmitin) of cytidine diphosphate diglyceride (CDP-diglyceride) in which the antitumor drug, cytosine arabinoside, is substituted for the cytidine moiety. Enzymes in rat and human liver convert this analog to phosphatidylinositol, thereby releasing cytosine arabinoside-5'-monophosphate, an obligatory intermediate in the activation of cytosine arabinoside. Unlike cytidine diphosphate diglyceride, however, ara-CDP-DL-diapalmitin is not an efficient substrate for phosphatidylglycerophosphate synthesis in liver or phosphatidylserine in Escherichia coli. The antitumor activity of ara-CDP-DL-dipalmitin in mice bearing L5178Y leukemia is described.
Recent Advances in Polymer Alloys and IPN Technology (1982)

<div class="htmlview paragraph">In this paper, we review the synthesis, morphology, and physical and mechanical properties of IPN’s as well as the related pseudo-IPN’s in which only one of the polymers is cross-linked. Recent studies have shown that the degree of phase separation achieved in these materials is strongly dependent on the compatibility of blends of the linear polymer constituents of the IPN components, as well as the kinetics of chain extension and the presence of grafting between component polymers. We illustrate this by a series of IPN’s consisting of a polyurethane and an acrylic copolymer. The acrylic is a typical automotive enamel. An enhancement in properties results which is dependent on the amount of grafting and the kinetics of polymerization. Also discussed are IPN’s of a polyurethane and an epoxy, which exhibited a synergism in adhesive properties, and IPN’s of a RIM polyurethane with several epoxies and unsaturated polyesters.</div>
The Evolving Role of Chemical Synthesis in Antibacterial Drug Discovery (2014)

The discovery and implementation of antibiotics in the early twentieth century transformed human health and wellbeing. Chemical synthesis enabled the development of the first antibacterial substances, organoarsenicals and sulfa drugs, but these were soon outshone by a host of more powerful and vastly more complex antibiotics from nature: penicillin, streptomycin, tetracycline, and erythromycin, among others. These primary defences are now significantly less effective as an unavoidable consequence of rapid evolution of resistance within pathogenic bacteria, made worse by widespread misuse of antibiotics. For decades medicinal chemists replenished the arsenal of antibiotics by semisynthetic and to a lesser degree fully synthetic routes, but economic factors have led to a subsidence of this effort, which places society on the precipice of a disaster. We believe that the strategic application of modern chemical synthesis to antibacterial drug discovery must play a critical role if a crisis of global proportions is to be averted.
Monolithic DBR-type fullband tunable lasers (2005)

This paper describes in detail the design and performance of the DS-DBR monolithic full band tunable laser and its application in tunable laser and transmitter modules
Variable digital filters (1980)

IIR prototype filters cannot be used for the design of variable filters through Schussler's all-pass transformation because of the occurrence of delay-free loops; no such problem arises with FIR prototypes. In this paper, the drawbacks of the latter type, with regard to computational efficiency and output roundoff noise, have been brought out, An approach is suggested, wherein the delay-free loops with IIR prototypes are eliminated by modifying the coefficients of the first- and second-order sections of the prototype filter. The computation of modified coefficients In this approach requires fewer multiplications as compared to an existing method.
Relative volatility of propane-propene system from 100-160.deg.F (1972)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRelative volatility of propane-propene system from 100-160.deg.FDale R. Laurance and George W. SwiftCite this: J. Chem. Eng. Data 1972, 17, 3, 333–337Publication Date (Print):July 1, 1972Publication History Published online1 May 2002Published inissue 1 July 1972https://pubs.acs.org/doi/10.1021/je60054a011https://doi.org/10.1021/je60054a011research-articleACS PublicationsRequest reuse permissionsArticle Views620Altmetric-Citations22LEARN 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 optionsGet e-Alertsclose Get e-Alerts
On <i>T</i><sub>2</sub>‐shortening by strongly magnetized spheres: A partial refocusing model (2002)

Computer simulations of water transverse relaxation induced by superparamagnetic particles are shown to disagree with the available theories, covering the slow diffusion domain. Understanding these new simulations, not in the slow diffusion domain, thus requires a new theoretical approach. A "partial refocusing model" is introduced for this purpose; it is based on a spatial division between an inner region where the gradients are too strong for the refocusing pulses to be efficient and an outer region where they are efficient. This model agrees with published simulations of relaxation induced by magnetic dipoles approximated as points. The validity domains of the various models are also compared.
CRISPR/Cas9-Based Genome Editing for Disease Modeling and Therapy: Challenges and Opportunities for Nonviral Delivery (2017)

Genome editing offers promising solutions to genetic disorders by editing DNA sequences or modulating gene expression. The clustered regularly interspaced short palindromic repeats (CRISPR)/associated protein 9 (CRISPR/Cas9) technology can be used to edit single or multiple genes in a wide variety of cell types and organisms in vitro and in vivo. Herein, we review the rapidly developing CRISPR/Cas9-based technologies for disease modeling and gene correction and recent progress toward Cas9/guide RNA (gRNA) delivery based on viral and nonviral vectors. We discuss the relative merits of delivering the genome editing elements in the form of DNA, mRNA, or protein, and the opportunities of combining viral delivery of a transgene encoding Cas9 with nonviral delivery of gRNA. We highlight the lessons learned from nonviral gene delivery in the past three decades and consider their applicability for CRISPR/Cas9 delivery. We also include a discussion of bioinformatics tools for gRNA design and chemical modifications of gRNA. Finally, we consider the extracellular and intracellular barriers to nonviral CRISPR/Cas9 delivery and propose strategies that may overcome these barriers to realize the clinical potential of CRISPR/Cas9-based genome editing.
The transition to turbulence in the wake of a circular cylinder (1964)

The position of the region of transition to turbulence and the manner in which turbulence develops are investigated using a hot-wire anemometer to study the character of the flow in the wake of a circular cylinder. In the range of Reynolds numbers greater than 200 in which turbulent motion is developed, the region of transition to turbulence moves towards the cylinder with increasing Reynolds number. The manner of transition to turbulence appears to undergo a basic change as the region of transition moves from the periodic wake into the region of flow immediately behind the cylinder where the separated layers have not rolled into vortices, that is, as the Reynolds number increases from Roshko's transition range to his irregular range. When transition occurs in the periodic wake it is a result of distortion due to large-scale three-dimensional effects. Turbulence, when it develops in the separated layers, is preceded by two-dimensional Tollmien-Schlichting waves which eventually degenerate to turbulence by the action of small-scale three-dimensionalities.
Friction Anisotropy with Respect to Topographic Orientation (2012)

Friction characteristics with respect to surface topographic orientation were investigated using surfaces of different materials and fabricated with grooves of different scales. Scratching friction tests were conducted using a nano-indentation-scratching system with the tip motion parallel or perpendicular to the groove orientation. Similar friction anisotropy trends were observed for all the surfaces studied, which are (1) under a light load and for surfaces with narrow grooves, the tip motion parallel to the grooves offers higher friction coefficients than does that perpendicular to them, (2) otherwise, equal or lower friction coefficients are found under this motion. The influences of groove size relative to the diameter of the mating tip (as a representative asperity), surface contact stiffness, contact area, and the characteristic stiction length are discussed. The appearance of this friction anisotropy is independent of material; however, the boundary and the point of trend transition depend on material properties.
Cholesterol and oxygenated cholesterol concentrations are markedly elevated in peripheral tissue but not in brain from mice with the Niemann–Pick type C phenotype (1998)

Abstract Niemann–Pick disease type C (NP‐C) is a rare genetic disorder characterized by progressive neurodegeneration, frequent developmental delay and early death. Tissues of affected individuals accumulate large quantities of free cholesterol in lysosomes. Because cytotoxic oxygenated derivatives of cholesterol are known to form readily when cholesterol concentrations are elevated, we searched for these compounds in liver, kidney, spleen and brain from mice with the NP‐C phenotype. In order of abundance, we identified 7α‐ and 7β‐hydroxycholesterol, 5α,6α‐epoxycholestan‐3β‐ol, 4β‐hydroxycholesterol, cholest‐4‐en‐3β,7α‐diol and cholest‐4‐en‐3β,6β‐diol in most tissue samples. Cholesterol concentrations in affected mice were increased 3‐fold in kidney and 7‐ to 8‐fold in spleen and liver compared to controls (all p<0.001) but were unchanged in brain. Although oxysterol levels were markedly elevated in non‐brain tissue, the oxysterol and cholesterol concentrations increased proportionally so that oxysterols expressed as percentage of total sterols were the same for all animals (0.34±0.19% averaged over all organs in affected animals vs 0.40±0.42% in control mice). In contrast to peripheral tissue, we could not detect any increase in either absolute or relative oxysterol levels in the brains of affected and control mice (49±61 vs 53±43 μg/g wet weight and 0.45±0.52 vs 0.47±0.37%, respectively). Thus, brain sterols are normal in NP‐C mice and it is unlikely that an accumulation of cytotoxic oxygenated derivatives of cholesterol could account for the progressive neuropathology seen in the disease.
Biosynthesis and Accumulation of Ergoline Alkaloids in a Mutualistic Association between <i>Ipomoea asarifolia</i> (Convolvulaceae) and a Clavicipitalean Fungus (2008)

Ergoline alkaloids occur in taxonomically unrelated taxa, such as fungi, belonging to the phylum Ascomycetes and higher plants of the family Convolvulaceae. The disjointed occurrence can be explained by the observation that plant-associated epibiotic clavicipitalean fungi capable of synthesizing ergoline alkaloids colonize the adaxial leaf surface of certain Convolvulaceae plant species. The fungi are seed transmitted. Their capacity to synthesize ergoline alkaloids depends on the presence of an intact differentiated host plant (e.g. Ipomoea asarifolia or Turbina corymbosa [Convolvulaceae]). Here, we present independent proof that these fungi are equipped with genetic material responsible for ergoline alkaloid biosynthesis. The gene (dmaW) for the determinant step in ergoline alkaloid biosynthesis was shown to be part of a cluster involved in ergoline alkaloid formation. The dmaW gene was overexpressed in Saccharomyces cerevisiae, the encoded DmaW protein purified to homogeneity, and characterized. Neither the gene nor the biosynthetic capacity, however, was detectable in the intact I. asarifolia or the taxonomically related T. corymbosa host plants. Both plants, however, contained the ergoline alkaloids almost exclusively, whereas alkaloids are not detectable in the associated epibiotic fungi. This indicates that a transport system may exist translocating the alkaloids from the epibiotic fungus into the plant. The association between the fungus and the plant very likely is a symbiotum in which ergoline alkaloids play an essential role.
Standards for holistic nursing practice: a way to think about our care that includes complementary and alternative modalities. (2001)

The Standards of Holistic Nursing Practice were developed by the American Holistic Nurses Association (AHNA) as a public statement regarding the practice of holistic nursing as a specialty. This article reviews the development of the practice standards, and presents the philosophies and values which underpin holistic nursing. Certification in the speciality is awarded through the American's Holistic Nurses' Certification Corporation (AHNCC) to nurses able to demonstrate knowledge and skills described in the Standards. The relationship between holistic nursing practice and complementary and alternative modalities is discussed.
Bulk AC-erasure technique for perpendicular recording media: effect of exchange coupling (2005)

We discuss a method of ac-demagnetizing an entire disk using permanent magnets and compare the demagnetized states of perpendicular media with different levels of intergranular exchange. The method consists of applying a large field perpendicular to the media recording layer anisotropy direction. This bulk ac-erasure technique provides a background noise that is lower than that which can be achieved by ac-erasing with a write head. Highly exchange-coupled media exhibit low dc noise but increased ac-erased background noise. Magnetic force microscopy data show increased magnetic roughness in the ac-erased state with exchange-coupling strength. For the media with least coupling the dc noise is similar to the ac noise.
Electrochemically Induced Hetero-[4+2]-Cycloaddition Reactions Between 2-Vinylpyrroles and -Acceptor-Substituted Enamines (1998)

An efficient route to indolizines is provided by radical-cation-initiated cycloaddition reactions between 2-vinylpyrroles acting as heterodienes and enamines (below; SET = single electron transfer).
Damage to sub-half-micron metal-oxide-silicon field-effect transistors from plasma processing of low- k polymer interlayer dielectrics (2000)

We report on the effects of via plasma etching of low-dielectric-constant (low-k ) polymers, used as interlayer dielectrics (ILDs), on the characteristics of sub-half-micron n-channel metal-oxide-silicon field-effect transistors (MOSFETs). The low-k polymers investigated are benzocylobutene and fluorinated poly-arylene-ether. The MOSFETs employed are made sensitive to via etching by incorporating an array of either 58 × 58 or 183 × 213 via holes to the gate electrode. We have found that the via etching of the polymer ILD damages the MOSFET as witnessed by the observed degradation in the transistor's parameter. The damage incurred by the MOSFET is of a charging type and is caused by plasma-induced stress current flowing into the gate oxide and oxide-Si interface through regions in the polymer ILD that are rendered leaky by the via etching plasma. We have observed that the inclusion of an insulating layer, such as Si3 N4 , can significantly inhibit the damaging effects of the via etch. Annealing at ~350 °C is found to eliminate the via-etch-induced damage and to improve the MOSFET's parameters.
Structure-function analysis of the antioxidant properties of haptoglobin (2001)

Haptoglobin serves as an antioxidant by virtue of its ability to prevent hemoglobin-driven oxidative tissue damage. It was recently demonstrated that an allelic polymorphism in the haptoglobin gene is predictive of the risk for numerous microvascular and macrovascular diabetic complications. Because these complications are attributed in large part to an increase in oxidative stress, a study was conducted to determine whether the different protein products of the 2 haptoglobin alleles differed in the antioxidant protection they provided. A statistically significant difference was found in the antioxidant capacity of purified haptoglobin protein produced from the 2 different alleles, consistent with the hypothesis that differences in genetically determined antioxidant status may explain differential susceptibility to diabetic vascular complications. These differences may be amplified in the vessel wall because of differences in the sieving capacity of the haptoglobin types. Therefore, an attempt was made to identify the minimal haptoglobin sequences necessary to inhibit oxidation by hemoglobin in vitro, and 2 independent haptoglobin peptides that function in this fashion as efficiently as native haptoglobin were identified. Identification of the biochemical basis for differences among haptoglobin types may lead to the rational development of new pharmacologic agents, such as the mini-haptoglobin described here, to avert the development of diabetic vascular complications.
Synthesis of 2′,3′-Dideoxyinosine (1988)

Abstract The synthesis of 2′,3′-dideoxyinosine (ddI, 1) from 2′-deoxyinosine and 2′,3′-dideoxyadenosine (ddA, 2) is described. Chemically, selective benzoylation of the 5′ hydroxyl group of 2′-deoxyinosine is followed by deoxy-genation at the 3′ position via the thioimidazolide 4. De-protection of the resulting 5′-O-benzoyl-2′,3′-dideoxyinosine 5 gave 2′,3′-dideoxyinosine 1. Enzymatically, deamination of ddA 2 with adenosine deaminase also yielded ddI.
Changing Enzymic Reaction Mechanisms by Mutagenesis: Conversion of a Retaining Glucosidase to an Inverting Enzyme (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChanging Enzymic Reaction Mechanisms by Mutagenesis: Conversion of a Retaining Glucosidase to an Inverting EnzymeQingping Wang, R. W. Graham, D. Trimbur, R. A. J. Warren, and S. G. WithersCite this: J. Am. Chem. Soc. 1994, 116, 25, 11594–11595Publication Date (Print):December 1, 1994Publication History Published online1 May 2002Published inissue 1 December 1994https://pubs.acs.org/doi/10.1021/ja00104a060https://doi.org/10.1021/ja00104a060research-articleACS PublicationsRequest reuse permissionsArticle Views840Altmetric-Citations132LEARN 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 optionsGet e-Alertsclose Get e-Alerts
Formation of columnar (In,Ga)As quantum dots on GaAs(100) (2004)

Columnar (In,Ga)As quantum dots (QDs) with homogeneous composition and shape in the growth direction are realized by molecular-beam epitaxy on GaAs(100) substrates. The columnar (In,Ga)As QDs are formed on InAs seed QDs by alternating deposition of thin GaAs intermediate layers and monolayers of InAs with extended growth interruptions after each layer. The height of the columnar (In,Ga)As QDs is controlled by varying the number of stacked GaAs∕InAs layers. The structural and optical properties are studied by cross-sectional scanning tunneling microscopy, atomic force microscopy, and photoluminescence spectroscopy. With increase of the aspect ratio of the columnar QDs, the emission wavelength is redshifted and the linewidth is reduced.