gebhart/patrepeval huggingface dataset:
Carbon Nanotubes Embedded in Oriented Polymer Nanofibers by Electrospinning (2003)

The electrospinning process was used successfully to fabricate nanofibers of poly(ethylene oxide) (PEO) in which multiwalled carbon nanotubes (MWCNT) are embedded. Initial dispersion of MWCNTs in water was achieved using amphiphiles, either as small molecules (sodium dodecyl sulfate, SDS) or as a high molecular weight, highly branched polymer (Gum Arabic). These dispersions provided separation of the MWCNTs and their individual incorporation into the PEO nanofibers by subsequent electrospinning. The focus of this work is on the development of axial orientations in these multicomponent nanofibers. A theoretical model is presented for the behavior of rodlike particles representing CNTs in electrospinning. Initially the rods are randomly oriented, but due to the sinklike flow in a wedge they are gradually oriented mainly along the stream lines, so that straight CNTs are almost oriented upon entering the electrospun jet. The degrees of orientation of polymer, surfactant, and MWCNT were studied using X-ray diffraction and transmission electron microscopy. Oriented ropes of the nanofibers were fabricated in a converging electric field by a rotating disk with a tapered edge. A high degree of alignment of PEO crystals was found in electrospun nanofibers containing only PEO, as well as PEO/SDS. The latter also exhibited a high degree of alignment of the SDS layers. The axial orientation of PEO and SDS is significantly reduced in MWCNT-containing nanofibers. Transmission electron microscopy (TEM) images indicated that the MWCNTs were embedded in the nanofibers as individual elements, mostly aligned along the fiber axis. Nevertheless, there are also many cases in which the nanotubes appear twisted, bent, or with other irregularities. Comparison of cryo-TEM images of vitrified MWCNT dispersions with TEM images of the raw nanotubes indicated that sonication during the dispersion process may be responsible for the irregularities observed in some of the nanotubes.
Biosynthesis of non-head-to-tail terpenes. Formation of 1'-1 and 1'-3 linkages (1990)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBiosynthesis of non-head-to-tail terpenes. Formation of 1'-1 and 1'-3 linkagesC. Dale PoulterCite this: Acc. Chem. Res. 1990, 23, 3, 70–77Publication Date (Print):March 1, 1990Publication History Published online1 May 2002Published inissue 1 March 1990https://pubs.acs.org/doi/10.1021/ar00171a003https://doi.org/10.1021/ar00171a003research-articleACS PublicationsRequest reuse permissionsArticle Views681Altmetric-Citations105LEARN 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
A Frame Aggregation Extension of Routing Algorithm for Wireless Mesh Networks (2014)

As a scalable Internet-access network, an Wireless Internet-access Mesh Network (WIMNET) consists of multiple wireless access-points (APs) that are connected through wireless links. At least one AP acts as a gateway (GW) to the Internet where any host must reach there through multi-hop communications between APs. To handle large traffics, the latest high-speed IEEE 802.11ac protocol should be adopted for scalable WIMNET, where the routing path determines the performance under its practical implementations using commercial products. Therefore, we have proposed a routing algorithm considering 1) multiple GWs, 2) the link speed change, and 3) the limited number of hops. In this paper, to further improve the performance, we extend the routing algorithm to efficiently consider the frame aggregation in IEEE802.11ac. We verify the effectiveness of our proposal through simulating two topologies using the extended WIMNET simulator.
Discovery of 1‐Hydroxypyridine‐2(1H)‐thione‐6‐carboxylic Acid as a First‐in‐Class Low‐Cytotoxic Nanomolar Metallo β‐Lactamase Inhibitor (2017)

VIM-2 is one of the most common carbapenem-hydrolyzing metallo β-lactamases (MBL) found in many drug-resistant Gram-negative bacterial strains. Currently, there is a lack of effective lead compounds with optimal therapeutic potential within our drug development pipeline. Here we report the discovery of 1-hydroxypyridine-2(1H)-thione-6-carboxylic acid (3) as a first-in-class metallo β-lactamase inhibitor (MBLi) with a potent inhibition K<sub>i</sub> of 13 nm against VIM-2 that corresponds to a remarkable 0.99 ligand efficiency. We further established that 3 can restore the antibiotic activity of amoxicillin against VIM-2-producing E. coli in a whole cell assay with an EC<sub>50</sub> of 110 nm. The potential mode of binding of 3 from molecular modeling provided structural insights that could corroborate the observed changes in the biochemical activities. Finally, 3 possesses a low cytotoxicity (CC<sub>50</sub> ) of 97 μm with a corresponding therapeutic index of 880, making it a promising lead candidate for further optimization in combination antibacterial therapy.
Regulation of growth factors in hormone‐ and drug‐resistant prostate cancer cells by synergistic combination of docetaxel and octreotide (2009)

OBJECTIVE To evaluate the effects of combined treatment with docetaxel and octreotide, a somatostatin analogue, on human hormone- and drug-refractory prostate cancer cell lines, PC-3 and DU-145, and on some growth factors related to tumour growth and angiogenesis in prostate cancer. MATERIALS AND METHODS A cell proliferation assay was used to assess the cytotoxicity of the drugs. To verify apoptosis, both DNA fragmentation (by enzyme-linked immunosorbent assay) and caspase 3/7 activity were measured. We also investigated the effect of combined docetaxel and octreotide on growth factors secreted from prostate cancer cells using a human growth factor antibody array. RESULTS The combination of docetaxel and octreotide resulted in significant synergistic cytotoxic activity and apoptosis, which was dose- and time-dependent. The combined treatment also resulted in significantly less secretion of stem cell factor and platelet-derived growth factor-AB in PC-3 cells, and transforming growth factor-beta and basic fibroblast growth factor in DU-145 cells, than in untreated controls. CONCLUSION Octreotide, a somatostatin analogue, combined with docetaxel might provide a rationale treatment option for hormone-refractory prostate cancer cells, not only by direct inhibition of cell proliferation but also by inhibiting the secretion of growth factors.
Influence of Cationic Substitutions on the Oxygen Loss and Reversible Capacity of Lithium-Rich Layered Oxide Cathodes (2011)

The influence of cationic substitutions on the ease with which oxygen loss occurs from lithium-rich layered oxide cathodes during first charge has been studied with three series of samples: Li[Li0.33Mn0.67−xTix]O2 (0 ≤ x ≤ 0.67), Li[Li0.2Mn0.54−xTixNi0.13Co0.13]O2 (0 ≤ x ≤ 0.27), and Li[Li0.2Mn0.60−xTixNi0.20]O2 (0 ≤ x ≤ 0.40). The lattice parameters and cell volume increase monotonically with the substitution of a larger Ti4+ for Mn4+, indicating the formation of solid solutions. It is found that substitution of Ti4+ for Mn4+ decreases the degree of oxygen loss and consequently the charge and discharge capacity values, while substitution of Co3+ for (Mn0.54+Ni0.52+) increases the oxygen loss and consequently the charge and discharge capacity values. While the former is attributed to a stronger binding of oxygen to Ti and a decrease in the metal−oxygen covalence due to a larger charge transfer gap between the Ti3+/4+ 3d and O2− 2p bands, the latter is attributed to a weaker binding of oxygen to Co and an increase in the metal−oxygen covalence due to an overlap of the Co3+/4+ t2g band with the top of the O2− 2p band.
Novel Therapy for Hearing Loss (2007)

These findings indicate that local rhIGF-1 treatment via gelatin hydrogels is effective for treatment of NIHL.
Differential diagnosis of macular breaks by microperimetry using the scanning laser ophthalmoscope. (1995)

To improve differential diagnosis of macular breaks, microperimetry with a scanning laser ophthalmoscope (SLO) was performed. Fifty consecutive macular breaks were detected by biomicroscopy and indirect ophthalmoscopy, and SLO microperimetry was performed on each. Of the 50 eyes, 22 eyes were diagnosed with idiopathic macular breaks by biopmicroscopy and indirect ophthalmoscopy because of a cuff. SLO microperimetry also showed dense scotoma within the macular break and relative scotoma on the cuff in the 22 eyes. However, diagnosis was not done only by biomicroscopy and indirect ophthalmoscopy in the other 28 eyes because of the absence of a cuff. SLO microperimetry differentiated the full thickness macular breaks from pseudo-or lamellar breaks in these eyes. SLO microperimetry is useful for differentiating their prognosis, and determining the need for surgical treatment.
Uncovering the Protocatechuate 2,3-Cleavage Pathway Genes (2009)

Paenibacillus sp. (formerly Bacillus macerans) strain JJ-1b is able to grow on 4-hydroxybenzoate (4HB) as a sole source of carbon and energy and is known to degrade 4HB via the protocatechuate (PCA) 2,3-cleavage pathway. However, none of the genes involved in this pathway have been identified. In this study, we identified and characterized the JJ-1b genes for the 4HB catabolic pathway via the PCA 2,3-cleavage pathway, which consisted of praR and praABEGFDCHI. Based on the enzyme activities of cell extracts of Escherichia coli carrying praI, praA, praH, praB, praC, and praD, these genes were found to code for 4HB 3-hydroxylase, PCA 2,3-dioxygenase, 5-carboxy-2-hydroxymuconate-6-semialdehyde decarboxylase, 2-hydroxymuconate-6-semialdehyde dehydrogenase, 4-oxalocrotonate (OCA) tautomerase, and OCA decarboxylase, respectively, which are involved in the conversion of 4HB into 2-hydroxypenta-2,4-dienoate (HPD). The praE, praF, and praG gene products exhibited 45 to 61% amino acid sequence identity to the corresponding enzymes responsible for the catabolism of HPD to pyruvate and acetyl coenzyme A. The deduced amino acid sequence of praR showed similarity with those of IclR-type transcriptional regulators. Reverse transcription-PCR analysis revealed that praABEGFDCHI constitute an operon, and these genes were expressed during the growth of JJ-1b on 4HB and PCA. praR-praABEGFDCHI conferred the ability to grow on 4HB to E. coli, suggesting that praEGF were functional for the conversion of HPD to pyruvate and acetyl coenzyme A. A promoter analysis suggested that praR encodes a repressor of the pra operon.
Mutants in disulfide bond formation that disrupt flagellar assembly in Escherichia coli. (1993)

We report the isolation and characterization of Escherichia coli mutants (dsbB) that fail to assemble functional flagella unless cystine is present. Flagellar basal bodies obtained from these mutants are missing the L and P rings. This defect in assembly appears to result from an inability to form a disulfide bond in the P-ring protein (FlgI). Cystine suppresses this defect in dsbB strains. We also show that dsbA strains [Bardwell, J. C. A., McGovern, K. & Beckwith, J. (1991) Cell 67, 581-589] fail to assemble P rings, apparently from a similar failure in disulfide bond formation. However, cystine does not completely suppress this defect in dsbA strains. Thus, disulfide bond formation in FlgI is essential for assembly. DsbA likely puts in that bond directly, whereas the DsbB product(s) play a role in oxidizing DsbA, so that it can be active.
Optimal deployment of mobile sensors for target tracking in 2D and 3D spaces (2014)

This paper proposes a control strategy to autonomously deploy optimal placements of range-only mobile sensors in 2D and 3D spaces. Based on artificial potential approaches, the control strategy is designed to minimize the intersensor and external potentials. The inter-sensor potential is the objective function for optimal sensor placements. A placement is optimal when the inter-sensor potential is minimized. The external potential is introduced to fulfill constraints on sensor trajectories. Since artificial potential approaches can handle various issues such as obstacle avoidance and collision avoidance among sensors, the proposed control strategy provides a flexible solution to practical autonomous optimal sensor deployment. The control strategy is applied to several optimal sensor deployment problems in 2D and 3D spaces. Simulation results illustrate how the proposed control strategy can improve target tracking performance.
Delineation of the amino acid residues involved in transcytosis and catabolism of mouse IgG1 (1997)

The MHC class I-related receptor, FcRn, is involved in both the transcytosis of serum gamma-globulins (IgGs) and in regulating their serum persistence. The interaction site of FcRn on the Fc region of rodent IgG has been mapped to residues at the CH2-CH3 domain interface using site-directed mutagenesis and x-ray crystallographic analyses. In the current study, the role of individual residues (H310, H433, and N434) at this interface in mediating the Fc-FcRn interaction has been investigated using recombinant, mutated Fc hinge fragments derived from mouse IgG1. In addition, two highly conserved Fc histidines (H435 and H436) have been mutated to alanine, and the resulting mutated Fc hinge fragments were analyzed in both transcytosis and pharmacokinetic studies in mice and in competition binding assays using recombinant, soluble FcRn. The analyses indicate that mutation of H310, H435, and, to a lesser extent, H436 to alanine results in reduced activity of the Fc hinge fragments in both in vivo and in vitro assays. Thus, in addition to the previously defined role of 1253 in the FcRn-IgG interaction, these histidines play a key role in mediating the functions conducted by this Fc receptor. The effects of these mutations on binding of Fc hinge fragments to staphylococcal protein A have also been analyzed and demonstrate a partial, but not complete, overlap of the FcRn and staphylococcal protein A interaction sites on mouse IgG1.
Tweaking Microtubules to Treat Scleroderma (2005)

van Laar and Huizinga discuss a new study of a mouse model of scleroderma, which showed that stabilizing microtubules with paclitaxel led to reduced fibrosis.
Cell-specific expression from the human dopamine beta-hydroxylase promoter in transgenic mice is controlled via a combination of positive and negative regulatory elements (1994)

The promoter region of the human dopamine beta-hydroxylase (DBH) gene was analyzed in transgenic mice to identify DNA sequences responsible for the tissue- and cell-specific expression of the gene. Transgenic mice were generated that carried the Escherichia coli lacZ gene under control of DBH promoter fragments between 0.6 and 5.8 kilobases (kb) in length. Sequences required for expression in adult and fetal noradrenergic neurons were located between 0.6 and 1.1 kb 5' to the DBH transcriptional start site. Sequences in this region and farther upstream also directed expression to dopaminergic and noncatecholaminergic brain neurons that was repressed by negative elements elsewhere in the gene. The results indicate that the neuron-specific expression of the DBH gene is mediated by positive regulatory elements but that negative elements are required to restrict expression to the proper subset of neurons.
Rapid and sensitive separation of trace level protein digests using microfabricated devices coupled to a quadrupole - time-of-flight mass spectrometer (2000)

The application of microfabricated devices coupled to a quadrupole time-of-flight mass spectrometer (Qq-TOF-MS) is presented for the analysis of trace level digests of gel-isolated proteins. In order to enhance the sample loading for proteomics analyses, two different on-chip sample preconcentration techniques were evaluated. First, a sample stacking procedure that used polarity switching to remove the sample buffer prior to zone electrophoresis was easily integrated on the microfabricated devices. With the present chip design, this preconcentration technique provided up to 70 nL sample injection with sub-nM detection limits for most peptide standards. For applications requiring larger sample loading, a disposable adsorption preconcentrator using a C18 membrane is incorporated outside the chip. This preconcentration method yielded lower peptide recoveries than that obtainable with sample stacking, and provided a convenient means of injecting several μL of sample with detection limits of typically 2.5 nM for hydrophobic peptides. The analytical merits of both sample enrichment approaches are described for the identification of bands isolated from two-dimensional (2-D) gel separation of protein extracts from Haemophilus influenzae. Accurate molecular mass measurements (< 5 ppm) in peptide mapping experiments is obtained by introducing an internal standard via a post-separation channel. Rapid identification of trace level peptides is also demonstrated using on-line tandem mass spectrometry and database searching with peptide sequence tags.
Use of a microwave cavity for sensing dielectric properties of arbitrarily shaped biological objects (1990)

A rectangular waveguide resonator operating in the H/sub 105/ mode at 3.2 GHz is used in determining the change in resonant frequency, Delta F, and the Q factor of the cavity, Delta T, when measured with and without single corn kernels of various shapes and dimensions. By measuring those variables for a kernel oriented in two positions differing by a 90 degrees rotation with respect to the maximum E-field vector, the average values of Delta F and Delta T are found to be independent of shape. The ratio Delta F/ Delta T is independent of size and is a function of the material properties ( epsilon '-1)/ epsilon ". This function is shown to be related to the material density, moisture content, or other characteristics when all other properties except the one selected remain unchanged.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Deoxycytidine triphosphate deaminase of Salmonella typhimurium. Purification and characterization (1975)

Deoxycytidine triphosphate deaminase (EC 3.5.4., dCTP aminohydrolase) of Salmonella typhimurium LT2 has been pruified 500-fold. The reaction requires the presence of Mg-2plus, Mn-2plus, Ca-2lus, or Co-2plus. Kinetics of the reaction with varying Mg-2plus concentrations, keeping the concentration of dCTP constant, suggests that the true substrate of the reaction is MgdCTP. The dependence of the rate of reaction on dCTP concentration in the presnece of 5-fold excess of Mg-2plus is sigmoid, with a Hill coefficient of 1.7. The enzyme is specifically inhibited by dTTP and dUTP. In the presence of increasing dTTP concentrations the sigmoidicity of the substrate saturation curves increases. With 0.2 and 0.4 mM dTTP the Hill coefficients are 2.6 and 3.0, respectively. Despite several attempts no dissociation of the substrate site and the inhibitor site of the enzyme was achieved.
Out with the old, in with the new? Comparing methods for measuring protein degradation (2011)

Protein degradation is a critical factor in controlling cellular protein abundance. Here, we compare classical methods for determining protein degradation rates to a novel GFP (green fluorescent protein) fusion protein based method that assesses the intrinsic stability of cloned cDNA library products by flow cytometry [Yen et al. (2008) Science 322, 918]. While no method is perfect, we conclude that chimeric gene reporter approaches, though powerful, should be applied cautiously, due principally to GFP (or other reporter tag) interference with protein organelle targeting or incorporation into macromolecular assemblies, both of which cause spuriously high degradation rates.
Developing a Hypercard-UNIX Interface for Electronic Mail Transfer (1992)

Abstract : The Hypercard-UNIX electronic mail system (HUES) was programmed using Hypercard version 1.2.5 on a Macintosh computer system. HUES was created as a user-friendly way for U.S. Army Human Engineering Laboratory (HEL) employees to transfer electronic mail, as well as files of various types and formats, to anyone connected to the Internet. (Note: The Internet is a collection of many networks that service universities, private industry, and the Department of Defense.) The system is essentially an interface or shell, which receives information from another computer system (in this case, a UNIX system) and displays the information in a format that allows easier user interaction with the UNIX system. The system receives information from another computer by using a group of transmission control protocol/Internet protocol (TCP/IP) code resources developed by Apple Computer, Inc., for use with Hypercard and Macintosh computer systems. This transfer of information allows users to take advantage of the Macintosh's point-and-click user interface to perform desired procedures, instead of having to type UNIX commands. The system was designed to be expandable, with two different means of establishing a connection to a host computer (i.e., modem or TCP/IP). The system also allows direct manipulation of UNIX files, (i.e., deleting, viewing) and the option of directly sending UNIX commands.
Anatomic standardization: linear scaling and nonlinear warping of functional brain images. (1994)

These results suggested that the method is well suited to both research and clinical settings and can facilitate pixel-by-pixel comparisons of PET images.
Organic electrochemical transistor incorporating an ionogel as a solid state electrolyte for lactate sensing (2012)

The bulk of the currently available biosensing techniques often require complex liquid handling, and thus suffer from problems associated with leakage and contamination. We demonstrate the use of an organic electrochemical transistor for detection of lactate (an essential analyte in physiological measurements of athlete performance) by integration of a room temperature ionic liquid in a gel-format, as a solid-state electrolyte.
Human B Cells Become Highly Responsive to Macrophage-Inflammatory Protein-3α/CC Chemokine Ligand-20 After Cellular Activation Without Changes in CCR6 Expression or Ligand Binding (2002)

CCR6 is the only known receptor for the chemokine macrophage-inflammatory protein (MIP)-3alpha/CC chemokine ligand (CCL)20. We have shown previously that CCR6 is expressed on peripheral blood B cells, but CCR6 activity on these cells is low in in vitro assays. We report that MIP-3alpha/CCL20-induced calcium flux and chemotaxis can be enhanced significantly on peripheral blood and tonsillar B cells after activation by cross-linking surface Ag receptors. Of particular interest is the fact that the enhanced activity on B cells was not associated with an increase in CCR6 expression as assessed by levels of receptor mRNA, surface staining, or MIP-3alpha/CCL20 binding sites, or by a change in the affinity of the receptor for ligand. These data convincingly demonstrate that responses to a chemokine can be regulated solely by changes in the downstream pathways for signal transduction resulting from Ag receptor activation, and establish CCR6 as an efficacious receptor on human B cells.