gebhart/patrepeval huggingface dataset:
Characterization and Partial Purification of the Acetylcholine Receptor from <i>Torpedo</i> Electroplax (1972)

Binding of acetylcholine in the concentration range 1 nM-1 muM was measured by equilibrium dialysis to a particulate preparation of Torpedo electroplax, without or with prior treatment of the tissue with one of three chemical modifying reagents. Significant reduction in binding of acetylcholine resulted after treatment with 1,4-dithiothreitol, p-chloromercuribenzoate, or p-(trimethylammonium)-benzenediazonium fluoroborate. Partial reversal of the reduction in binding occurred when dialysis was performed in the presence of 5,5'-dithiobis-(2-nitrobenzoic acid) or potassium ferricyanide (in the case of treatment with dithiothreitol), and 2-mercaptoethanol (in the case of treatment with p-chloromercuribenzoate). It is concluded that the functional acetylcholine-receptor macromolecule of Torpedo electroplax has disulfide bond(s), sulfhydryl group(s), and one or more of the amino acids vulnerable to diazotization by p-(trimethylammonium)-benzenediazonium fluoroborate. This, plus the effect of phospholipase C (EC 3.1.4.3) in elimination of detectable binding of acetylcholine after electrofocusing, is additional evidence that the functional acetylcholine receptor is a phospholipoprotein or a phospholipid-protein complex, which has a low isoelectric point of 4.5 +/- 0.2, yet is denatured by exposure to low pH for 24 hr. Due to this adverse effect, recovery of binding of acetylcholine after electrofocusing, as detected by equilibrium dialysis or ultrafiltration, is only 23% and, so far, only 6.3-fold purification of functional acetylcholine receptors by this technique is possible. Three or two forms of acetylcholinesterase (EC 3.1.1.7), whose peaks have isoelectric points ranging from 4.3 to 7.2, appear after electrofocusing of Torpedo extracted with 1% Triton X-100 or Lubrol, respectively. The major peak in either preparation has an isoelectric point of 5. Although the peaks of the functional acetylcholine receptors and of acetylcholinesterase of Torpedo electroplax are separable by electrofocusing, it has not been possible to isolate fractions that contain functional receptors but that are free of acetylcholinesterase. The opposite is possible.
Inhibition of Breast Cancer Metastasis by Presurgical Treatment with an Oral Matrix Metalloproteinase Inhibitor: A Preclinical Proof-of-Principle Study (2016)

Breast cancer has the second highest death toll in women worldwide, despite significant progress in early diagnosis and treatments. The main cause of death is metastatic disease. Matrix metalloproteinases (MMP) are required for the initial steps of metastasis, and have therefore been considered as ideal pharmacologic targets for antimetastatic therapy. However, clinical trials of MMP inhibitors were unsuccessful. These trials were conducted in patients with advanced disease, beyond the stage when these compounds could have been effective. We hypothesized that early treatment with a selective MMP inhibitor between the time of diagnosis and definitive surgery, the so-called "window-of-opportunity," can inhibit metastasis and thereby improve survival. To investigate our hypothesis, we used the 4T1 mouse model of aggressive mammary carcinoma. We treated the animals with SD-7300, an oral inhibitor of MMP-2, -9, and -13, starting after the initial detection of the primary tumor. Seven days later, the primary tumors were excised and analyzed for MMP activity, and the SD-7300 treatment was discontinued. After 4 weeks, the animals were sacrificed and their lungs analyzed histologically for number of metastases and metastatic burden (metastases' area/lung section area). SD-7300 treatment inhibited 70% to 80% of tumor-associated MMP activity (P = 0.0003), reduced metastasis number and metastatic burden by 50% to 60% (P = 0.002 and P = 0.0082, respectively), and increased survival (92% vs. 66.7%; P = 0.0409), relative to control vehicle. These results show that treatment of early invasive breast cancer with selective MMP inhibitors can lower the risk of recurrence and increase long-term disease-free survival. Mol Cancer Ther; 15(10); 2370-7. ©2016 AACR.
Measurements of BET Surface Area on Silica Nanosprings (2008)

Nitrogen adsorption desorption isotherm for Silica nanosprings (GoNano2) samples deposited on substrate. The isotherm was obtained at 77 K using liquid N2 bath. The area of the substrate is 16 cm2. The amount of the sample is 0.44 mg/cm2. Amount of silica nanosprings= 7.04 mg. There is no indication of substantial micro or mesoporosity in the sample based on the nature of the isotherm. Eleven point BET surface area was measured. Nine points plotted. Goodness if fit R= 0.9992. BET surface area for silica nanosprings= 262 cm2/g
Transgenic Mice Expressing Human Fetal Globin Are Protected From Malaria by a Novel Mechanism (1998)

Studies in vitro by Pasvol et al (Nature, 270:171, 1977) have indicated that the growth of Plasmodium falciparum in cells containing fetal hemoglobin (HbF = alpha2gamma2) is retarded, but invasion is increased, at least in newborn cells. Normal neonates switch from about 80% HbF at birth to a few percent at the end of the first year of life. Carriers of beta-thalassemia trait exhibit a delay in the normal HbF switch-off, which might partially explain the protection observed in populations with this gene. To study this hypothesis in vivo, we used transgenic (gamma) mice expressing human Agamma and Ggamma chains resulting in 40% to 60% alpha2Mgamma2 hemoglobin, infected with rodent malaria. Two species of rodent malaria were studied. P chabaudi adami causes a nonlethal infection, mainly in mature red blood cells (RBC). P yoelii 17XNL is a nonlethal infection, invading primarily reticulocytes, whereas P yoelii 17XL is a lethal variant of P yoelii 17XNL and causes death of mice in approximately 1 to 2 weeks. Data indicate that this strain may cause a syndrome resembling cerebral malaria caused by P falciparum (Am J Trop Med Hyg, 50:512, 1994). In gamma transgenic mice infected with P chabaudi adami, the parasitemia rose more quickly (in agreement with Pasvol) than in control mice, but was cleared more rapidly. In mice infected with P yoelii 17XNL, a clear reduction in parasitemia was observed. Interestingly, splenectomy before this infection, did not reverse protection. The most striking effect was in lethal P yoelii 17XL infection. Control mice died between 11 to 13 days, whereas gamma mice cleared the infection by day 22 and survived, a phenomenon also observed in splenectomized animals. These results suggest that HbF does indeed have a protective effect in vivo, which is not mediated by the spleen. In terms of mechanisms, light microscopy showed that intraerythrocytic parasites develop slowly in HbF erythrocytes, and electron microscopy showed that hemozoin formation was defective in transgenic mice. Finally, digestion studies of HbF by recombinant plasmepsin II demonstrated that HbF is digested only half as well as hemoglobin A (HbA). We conclude that HbF provides protection from P falciparum malaria by the retardation of parasite growth. The mechanism involves resistance to digestion by malarial hemoglobinases based on the data presented and with the well-known properties of HbF as a super stable tetramer. In addition, the resistance of normal neonates for malaria can now be explained by a double mechanism: increased malaria invasion rates, reported in neonatal RBC, will direct parasites to fetal cells, as well as F cells, and less to the approximately 20% of HbA containing RBC, amplifying the antimalarial effects of HbF.
Cognitive DISH: Virtual Spectrum Sensing Meets Cooperation (2009)

Cognitive radio technology increases spectrum utilization by enabling secondary users to opportunistically use the spectrum when primary users are inactive. Secondary users use spectrum sensing to detect the presence of primary users in order to avoid causing harmful interference. To the best of our knowledge, all existing spectrum sensing methods are essentially physical spectrum sensing, in the sense that nodes physically tune their radio to each frequency band to sense the spectrum. In this paper, we propose a complementary approach, virtual spectrum sensing, which achieves the same goal but only senses a very small portion of the spectrum. This approach enables a Distributed Information SHaring (DISH) mechanism, where neighboring users cooperatively share spectrum usage information (obtained from virtual spectrum sensing) with users who need it in decision making. This paper presents an application of DISH to cognitive radio networks. We provide a Cognitive DISH framework which describes guidelines for cognitive radio protocol design based on virtual spectrum sensing and DISH. Under this framework, we design a protocol, VISH-I, and evaluate its performance via simulations. As the number of secondary users increases, the interference caused to primary users results in only 5% performance degradation, but the overall channel utilization is increased by 87-203%. In addition, to demonstrate that virtual sensing is complementary to physical sensing, we design a hybrid spectrum sensing protocol, VISH-II, which improves performance by 7-50% over VISH-I.
Crossover experiments and the mechanism of substitution of metal-metal-bonded carbonyls (1982)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCrossover experiments and the mechanism of substitution of metal-metal-bonded carbonylsSteven P. Schmidt, William C. Trogler, and Fred BasoloCite this: Inorg. Chem. 1982, 21, 4, 1698–1699Publication Date (Print):April 1, 1982Publication History Published online1 May 2002Published inissue 1 April 1982https://pubs.acs.org/doi/10.1021/ic00134a094https://doi.org/10.1021/ic00134a094research-articleACS PublicationsRequest reuse permissionsArticle Views121Altmetric-Citations15LEARN 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
Air Movement and Contaminant Control from Water Sprays (2011)

Abstract A significant part of industrial hygiene research and development in the United States is directed towards mining. Most of this mining-related research is done by the U.S. Department of the Interior's Bureau of Mines, which receives funding for health and safety research amounting to $30 to $35 million annually. The work is primarily directed towards coal miners, who have traditionally suffered the highest fatality and accident frequency rates of any industry. Health problems are also no stranger to the miner. Coal worker's pneumoconiosis, or “black lung” disease, has exacted an unprecedented toll of tens of thousands of lives. Black lung compensation costs about $2 billion every year. Although much of the worst is behind us, the coal mine still leaves much to be desired when compared to the factory floor visited by the typical industrial hygienist. Some of the Bureau's research could be adapted by other industries. I have volunteered to contribute a little to the technology transfer process by h...
Cu Segregation around Metastable Phase in Al-Mg-Si Alloy with Cu (2007)

Cu distribution around Q′-phase in an Al-1.0 mass% Mg2Si-0.5 mass% Cu alloy has been investigated by the analytical transmission electron microscope (TEM), energy-filtering TEM (EFTEM), and high angular annular dark field scanning TEM (HAADF-STEM) techniques in order to determine the effect of Cu on the precipitation of this alloy. Cu-segregation around rod-shaped precipitates in the sample aged at 523 K for 24 ks was confirmed by energy dispersive X-ray spectroscopy, elemental maps, and HAADF-STEM images. Cu-segregation was also detected from small precipitates, which show a hexagonal network with a lattice constant of 1.04 nm in their HRTEM images. Coarse rods show homogeneous distribution of Cu, and chemical composition is similar to that of coarse Q′- or Q-phase. Small precipitates less than 10 nm were also confirmed in as-quenched samples, and those precipitates seem to form during quenching.
Extended Interferon-Alpha Therapy Accelerates Telomere Length Loss in Human Peripheral Blood T Lymphocytes (2011)

Sustained interferon-alpha treatment increased telomere loss in naïve T cells, and inhibited the accumulation of T cell memory expansions. The durability of this effect and consequences for immune senescence need to be defined.
Characterization of the Behavior of a Pyrene Substituted Gemini Surfactant in Water by Fluorescence (2011)

Time-resolved fluorescence was applied to characterize the behavior in solution of a gemini surfactant substituted with pyrene (Py-3-12). Upon association in water, excimer formation by Py-3-12 can be probed by acquiring pyrene monomer and excimer fluorescence decays which can be fitted globally according to the model free (MF) analysis to yield quantitative information about the internal dynamics of the Py-3-12 surfactant micelles as well as a complete description of the distribution of the different pyrene species in solution either incorporated inside the micelles or free in solution. A proof of procedure for the MF analysis was established by noting that the concentrations of free surfactant in solution, [Py-3-12](free), was found to equal the critical micelle concentration (CMC) for surfactant concentrations larger than the CMC. (I(E)/I(M))(SPC), the ratio of pyrene monomer to excimer fluorescence intensities, was calculated from parameters retrieved from the MF analysis of the fluorescence decays and was found to be independent of sample geometry. This work demonstrates how time-resolved fluorescence can be used to study the properties of pyrene-labeled macromolecules under conditions where large absorptions and inner filter effects usually distort the steady-state fluorescence signals. It was found that the pyrene excimer is formed mostly by diffusion within the Py-3-12 micelles, which suggests that the pyrene microenvironment is fluid, an important feature for future studies on the interactions of Py-3-12 with DNA.
Developing and accessing scientific databases with the OPM data management tools (1997)

Summary form only given. The Object-Protocol Model (OPM) data management tools provide facilities for rapid development, documentation, and flexible exploration of scientific databases. The tools are based on OPM, an object-oriented data model which is similar to the ODMG standard, but also supports extensions for modeling scientific data. Databases designed using OPM can be implemented using a variety of commercial relational DBMSs, using schema translation tools that generate complete DBMS database definitions from OPM schemas. Further, OPM schemas can be retrofitted on top of existing databases defined using a variety of notations, such as the relational data model or the ASN.1 data exchange format, using OPM retrofitting tools. Several archival molecular biology databases have been designed and implemented using the OPM tools, including the Genome Database (GDB) and the Protein Data Bank (PDB), while other scientific databases, such as the Genome Sequence Database (GSDB), have been retrofitted with semantically enhanced views using the OPM tools.
Beobachtungen an Befestigungsanlagen in Katalonien : Elemente griechischer Befestigungstechnik in Emporion, Ullastret und Tivissa (2020)

Deutsche Zusammenfassung folgt.
Free-Radical Co-Oligomerization of N-Vinylpyrroles with N-Vinylpyrrolidone: A Route to New Bioactive Oligomers (2018)

Co-oligomerization of N-vinylpyrroles (N-vinyl-2,3-dimethylpyrrole, N-vinyl-2-phenylpyrrole, N-vinyl-2,3-diphenylpyrrole, N-vinyl-2-(2-thienyl)pyrrole, and N-vinyl-2-[1-(4,5,6,7-tetrahydroindolyl) ethyl]-4,5,6,7-tetrahydroidole) with N-vinylpyrrolidone in the presence of a radical initiator (AIBN) gives co-oligomers with molecular masses of 1600–5200 in up to 87% yield. The products are readily soluble in organic solvents (benzene, 1,4_dioxane, and chloroform), and in the case of high N-vinylpyrrolidone content, also in ethanol and in water. The co-oligomers are non-toxic or have low toxicity (the lethal dose LD50 = 1300–2000) and possess biological activity.
ChemInform Abstract: Synthesis of a Novel Ring‐Expanded Xanthine Analogue and Several Methyl or Benzyl Derivatives Containing the 5:7‐Fused Imidazo(4,5‐e)(1, 2,4)triazepine Ring System. (1991)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
EVALUATION OF FATIGUE CRITERIA FOR ASPHALT BINDERS (WITH DISCUSSION AND CLOSURE) (2001)

The original Superpave asphalt binder specification criterion for fatigue, G* sin delta, has received considerable criticism. Recently, a time sweep using the dynamic shear rheometer (DSR) has been proposed as an alternative test method for developing load-associated fatigue information for asphalt binders. This proposed test method is examined with respect to a phenomenon called edge fracture. Edge fracture is reported in the literature for steady state and oscillatory flow in DSR, but it has not been reported for asphalt binders. The modulus, when plotted versus number of cycles generated in a time sweep test (repeated shear test), has the appearance typical of fatigue behavior; however, the actual response of the material depends markedly on the initial modulus of the material. The development of the modulus with repeated shearing is described with respect to flow of the asphalt binder at its circumference. The data are examined with respect to their validity as a measure of fatigue, and recommendations with respect to the use of time sweep data in a binder specification are presented.
Chiral Recognition on Catalytic Surfaces: Theoretical Insight in a Biomimetic Heterogeneous Catalytic System (2008)

Docking of molecules to surface chiral sites generated by adsorbed chiral organic modifiers is a fundamental step in heterogeneous metal-catalyzed asymmetric hydrogenation. The understanding of such docking events is nonetheless limited by the technical difficulties in obtaining experimental submolecular information for complex adsorbed structures. In addition an accurate theoretical analysis is computationally very demanding due to the need of including the metal surface. The present investigation explores by means of density functional theory the supramolecular docking structures of ketopantolactone within the chiral sites formed by cinchonidine adsorbed on a platinum surface, a crucial step in the enantioselective hydrogenation of ketopantolactone over cinchonidine-modified platinum. The study is performed using periodic slabs exposing Pt(111) surfaces of (6 × 6) and (8 × 8) atoms with a depth of four layers and including complete relaxation of the first three. Twenty six docking sites are investigated thus covering the most complete configurational space until now. The implications of the physi- and chemisorption of ketopantolactone in the docking have been also explored, thus revealing the role of weak and strong adsorption of the substrate in the formation of precursor states for hydrogen uptake within a docking site. The calculations on the (8 × 8) periodic slab were performed in order to decouple the energy related to the adsorption of the substrate from the energy involved in the docking interactions with the adsorbed alkaloid. Such a surface is in fact apt to accommodate both the chiral surface site and the noninteracting substrate. The study revealed that the substrate likely approaches the chiral site either from solution or from the physisorbed state. The resulting scenario gives a basic understanding of the elements involved in the docking of substrates within the chiral sites formed by cinchona alkaloids on platinum, and constitutes a fundamental stage for the comprehensive clarification of enantioselectivity at chirally modified surfaces.
Efficient organic light-emitting diodes with undoped active layers based on silole derivatives (2002)

We report on efficient molecular organic light-emitting diodes (MOLEDs) composed of novel silole derivatives as an electron transporting layer and an emissive layer. The silole derivative, 2,5-bis(2′,2″-bipyridin-6-yl)-1,1-dimethyl-3,4-diphenylsilacyclopentadiene, used for the electron transport layer exhibits fast electron mobility of 2×10−4 cm2/V s at 0.64 MV/cm measured by the time-of-flight technique. Another silole derivative, 1,2-bis(1-methyl-2,3,4,5-tetraphenyl silacyclopentadienyl)ethane, used for an emissive layer exhibits blue-green fluorescence with an absolute quantum yield of 97±3% in the solid state. The devices using silole derivatives show a very low operating voltage, an external electroluminescence quantum efficiency (ηEL) of 4.8 %, and luminous power efficiency of 9 lm/W at a brightness of 100 cd/m2. This value of ηEL is the best efficiency achieved for MOLED using undoped emissive and carrier transport layers and is close to the theoretical limit for a device using a fluorescent emitter.
L-type Voltage-Gated Ca <sup>2+</sup> Channels Modulate Expression of Smooth Muscle Differentiation Marker Genes via a Rho Kinase/Myocardin/SRF–Dependent Mechanism (2004)

Vascular smooth muscle cell (SMC) contraction is mediated in part by calcium influx through L-type voltage-gated Ca2+ channels (VGCC) and activation of the RhoA/Rho kinase (ROK) signaling cascade. We tested the hypothesis that Ca2+ influx through VGCCs regulates SMC differentiation marker expression and that these effects are dependent on RhoA/ROK signaling. Depolarization-induced activation of VGCCs resulted in a nifedipine-sensitive increase in endogenous smooth muscle myosin heavy chain (SMMHC) and SM alpha-actin expression and CArG-dependent promoter activity, as well as c-fos promoter activity. The ROK inhibitor, Y-27632, prevented depolarization-induced increase in SMMHC/SM alpha-actin but had no effect on c-fos expression. Conversely, the Ca2+/calmodulin-dependent kinase inhibitor, KN93, prevented depolarization-induced increases in c-fos expression with no effect on SMMHC/SM alpha-actin. Depolarization increased expression of myocardin, a coactivator of SRF that mediates CArG-dependent transcription of SMC marker gene promoters containing paired CArG cis regulatory elements (SMMHC/SM alpha-actin). Both nifedipine and Y-27632 prevented the depolarization-induced increase in myocardin expression. Moreover, short interfering RNA (siRNA) specific for myocardin attenuated depolarization-induced SMMHC/SM alpha-actin transcription. Chromatin immunoprecipitation (ChIP) assays revealed that depolarization increased SRF enrichment of the CArG regions in the SMMHC, SM alpha-actin, and c-fos promoters in intact chromatin. Whereas Y-27632 decreased basal and depolarization-induced SRF enrichment in the SMMHC/SM alpha-actin promoter regions, it had no effect of SRF enrichment of c-fos. Taken together, these results provide evidence for a novel mechanism whereby Ca2+ influx via VGCCs stimulates expression of SMC differentiation marker genes through mechanisms that are dependent on ROK, myocardin, and increased binding of SRF to CArG cis regulatory elements.