gebhart/patrepeval huggingface dataset:
Crucial role of intralobe peptide-peptide interactions in the uptake and release of iron by ovotransferrin. (1994)

The mechanism for reversible iron binding in the N-terminal lobe of ovotransferrin was investigated by a protein fragmentation approach. The iron-saturated N-terminal half-molecule of ovotransferrin was proteolyzed into large 30-kDa (1-279) and small 6-kDa (280-332) fragments by a single cleavage with Achromobacter protease I, producing a stable nicked form. For the separation of the two fragments, denaturing conditions were required. The isolated large fragment contained all four iron-coordinating ligands and the anion-binding ligand, and according to spectroscopic titration analysis, it showed iron binding capacity. The iron-bound large fragment, however, showed a blue-shifted visible absorption spectrum and a much decreased iron stability compared with those of the intact half-molecule. Analyses by ion-exchange chromatography revealed that the large fragment reassociates with the small fragment. In order for reassociation to occur, iron must be bound to the large fragment; upon reassociation, the large fragment regained its stable iron binding capacity as well as a visible absorption spectrum almost indistinguishable from those of the intact half-molecule. These data are consistent with a two-step sequential pathway for reversible iron binding in the N-terminal lobe of ovotransferrin that includes an initial iron binding intermediate having a perturbed metal environment and its transformation into the stable iron-bound holoform by peptide-peptide interactions between the large coordinating and small noncoordinating segments.
Syntheses and Physical Characterization of New Aliphatic Triblock Poly(<scp>l</scp>-lactide-<i>b</i>-butylene succinate-<i>b</i>-<scp>l</scp>-lactide)s Bearing Soft and Hard Biodegradable Building Blocks (2003)

This study presents chemical syntheses and physical characterization of a new aliphatic poly(L-lactide-b-butylene succinate-b-L-lactide) triblock copolyester with soft and hard biodegradable building blocks. First, poly(butylene succinate) (PBS) prepolymers terminated with hydroxyl functional groups were synthesized through melt polycondensation from succinic acid and 1,4-butanediol. Further, a series of new PLLA-b-PBS-b-PLLA triblock copolyesters bearing various average PLLA block lengths were prepared via ring opening polymerization of L-lactide with the synthesized hydroxyl capped PBS prepolymer (Mn = 4.9 KDa) and stannous octanoate as the macroinitiator and catalyst, respectively. By means of GPC, NMR, FTIR, DSC, TGA, and wide-angle X-ray diffractometer (WAXD), the macromolecular structures and physical properties were intensively studied for these synthesized PBS prepolymer and PLLA-b-PBS-b-PLLA triblock copolyesters. 13C NMR and GPC experimental results confirmed the formation of sequential block structures without any detectable transesterification under the present experimental conditions, and the molecular weights of triblock copolyesters could be readily regulated by adjusting the feeding molar ratio of L-lactide monomer to the PBS macroinitiator. DSC measurements showed all single glass transitions, and their glass transition temperatures were found to be between those of PLLA and PBS, depending on the lengths of PLLA blocks. It was noteworthy that the segmental flexibilities of the hard PLLA blocks were found to be remarkably enhanced by the more flexible PBS block partner, and the PBS and PLLA building blocks were well mixed in the amorphous regions. Results of TGA analyses indicated that thermal degradation and stabilities of the PLLA blocks strongly depended on the average PLLA block lengths of triblock copolyesters. In addition, FTIR and WAXD results showed the coexistence of the assembled PLLA and PBS crystal structures when the average PLLA block length became larger than 7.8. These results may be beneficial for this new biodegradable aliphatic triblock copolyester to be applied as a potential biomaterial.
ChemInform Abstract: SMALL RINGS. 26. CYCLOADDITION OF VINYL AZIRIDINES WITH UNSATURATED SUBSTRATES. A NOVEL REARRANGEMENT OF AN UNSATURATED NITRO COMPOUND (1982)

Abstract 2‐Phenyl‐azirin (I) ergibt mit Vinylmagnesiumbromid (II) die Vinylverbindung (III), die sich mit Acetylendicarbonsäureester (IV) zum Dihydroazepin (V) umsetzt.
Image-Converter Cameras For Laser And Laser-Plasma Diagnostics (1977)

Described here is the development of various hir7h-spe,,d image-converter cameras(TCC)in-tended for laser and laser plasma diagnostics. The complete set of th designed cameras covred in the linear streak mode the overall recording range of 10-2- 10-10 s and 10-12 - 5.10-9 s in the single-frame mode. The maximum streak temporal resolution is about -1 10 s in the visible and near infrared spectral region. Special attention was paid to 10-11 the high-speed ICC which provided the maximum streak resolution close to (1-3)•10 A and the minimum sinale-frame exposure of the order of 10-9 s in the 1-10 A spectral range. Cameras technical performances as well as their pulsed and supply electronics are brief-ly discussed.T:entioned also are some aspects of the ICC application in laser experirents.© (1977) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Gene Expression Profiling of Rat Brain Neurons Reveals Angiotensin II-Induced Regulation of Calmodulin and Synapsin I: Possible Role in Neuromodulation* (2001)

Angiotensin (Ang II) activates neuronal AT(1) receptors located in the hypothalamus and the brainstem and stimulates noradrenergic neurons that are involved in the control of blood pressure and fluid intake. In this study we used complementary DNA microarrays for high throughput gene expression profiling to reveal unique genes that are linked to the neuromodulatory actions of Ang II in neuronal cultures from newborn rat hypothalamus and brainstem. Of several genes that were regulated, we focused on calmodulin and synapsin I. Ang II (100 nM; 1-24 h) elicited respective increases and decreases in the levels of calmodulin and synapsin I messenger RNAs, effects mediated by AT(1) receptors. This was associated with similar changes in calmodulin and synapsin protein expression. The actions of Ang II on calmodulin expression involve an intracellular pathway that includes activation of phospholipase C, increased intracellular calcium, and stimulation of protein kinase C. Taken together with studies that link calmodulin and synapsin I to axonal transport and exocytotic processes, the data suggest that Ang II regulates these two proteins via a Ca(2+)-dependent pathway, and that this may contribute to longer term or slower neuromodulatory actions of this peptide.
Development Status of the HiVHAC Hall Thruster (2008)

The High Voltage Hall Accelerator (HiVHAC) development program task, funded by the NASA Science Mission Directorate's In-Space Propulsion Technology Program, is advancing the current state-of-the-art Hall thruste r's performance, life and cost. Its goal is to meet and/or exceed the requirements of Discovery class missions by developing a thruster that operates over a range of input powers from 0.3 to 3.5 kW, that can operate at specific impulses from 1,000 to 2,800 s, and that can proces s 300 kg of propellant while operating at full power. The HiVHAC program is currently building upon a history of design, analysis, fabrication, and test experience gained from a seri es of experimental investigations over the last several years. The latest design is the NASA- 103M.XL (eXtended Life) Hall thruster. This thruster incorporates design features enabling a projected lifetime in excess of 15,000 hours at a power level of 3.5 kW. A laboratory model of the NASA-103M.XL has demonstrated > 4,000 hours of wear testing at a dis charge voltage of 700 V. The next task of the HiVHAC program is to evolve this design into an engineering model thruster capable of demonstrating TRL-6 readiness. This paper will focus on the development status of the engineering model design.
Utilization of Plasticizers and Related Organic Compounds by Fungi (1957)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTUtilization of Plasticizers and Related Organic Compounds by FungiSigmund Berk, Helen Ebert, and Leonard TeitellCite this: Ind. Eng. Chem. 1957, 49, 7, 1115–1124Publication Date (Print):July 1, 1957Publication History Published online1 May 2002Published inissue 1 July 1957https://pubs.acs.org/doi/10.1021/ie50571a035https://doi.org/10.1021/ie50571a035research-articleACS PublicationsRequest reuse permissionsArticle Views100Altmetric-Citations43LEARN 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 options Get e-Alerts
Post-verification debugging of hierarchical designs (2005)

As VLSI designs grow in complexity and size, errors become more frequent and difficult to track. Recent developments have automated most of the verification tasks but debugging still remains a resource-intensive, manually conducted procedure. This paper bridges this gap as it develops robust automated debugging methodologies that complement verification processes. Unlike prior debugging techniques, the proposed one exploits the hierarchical nature of modern designs to improve the performance and quality of debugging. It also formulates the problem in terms of Quantified Boolean Formula Satisfiability to obtain dramatic reduction in memory requirements, which allows for debugging of large designs. Extensive experiments conducted on industrial and benchmark designs confirm the efficiency and practicality of the proposed approach.
Conserved developmental expression of Fezf in chordates and Drosophila and the origin of the Zona Limitans Intrathalamica (ZLI) brain organizer (2010)

The absence of expression of the corresponding morphogens from cells at these conserved genetic boundaries in invertebrates suggests that the organizing properties might have evolved specifically in the vertebrate lineage by the recruitment of key morphogens to these conserved genetic locations.
Vesicle formation in electrolyte solutions of a new cationic siloxane surfactant (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTVesicle formation in electrolyte solutions of a new cationic siloxane surfactantZ. Lin, M. He, L. E. Scriven, H. T. Davis, and S. A. SnowCite this: J. Phys. Chem. 1993, 97, 14, 3571–3578Publication Date (Print):April 1, 1993Publication History Published online1 May 2002Published inissue 1 April 1993https://pubs.acs.org/doi/10.1021/j100116a022https://doi.org/10.1021/j100116a022research-articleACS PublicationsRequest reuse permissionsArticle Views387Altmetric-Citations35LEARN 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 options Get e-Alerts
Synthesis of 2-azetidinones (1969)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of 2-azetidinonesJack N. Wells and Robert E. LeeCite this: J. Org. Chem. 1969, 34, 5, 1477–1479Publication Date (Print):May 1, 1969Publication History Published online1 May 2002Published inissue 1 May 1969https://pubs.acs.org/doi/10.1021/jo01257a067https://doi.org/10.1021/jo01257a067research-articleACS PublicationsRequest reuse permissionsArticle Views123Altmetric-Citations10LEARN 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
Real-Time Underwater Positioning and Navigation of an AUV in Deep Waters (2018)

Due to the absence of GPS, navigation of autonomous vehicles underwater requires the integration of various measurements to provide the best location estimate. Usually in littoral waters, adequate navigational accuracy may be obtained by integrating odometry measurements provided by a Doppler Velocity Log (DVL) into an Inertial Navigation System (Aided INS). However, due to the bulk attenuation of seawater at the acoustic centre frequency at which DVLs typically operate, odometry estimates become increasingly unreliable when the vehicle flies more than 200 m above the bottom (depending on the DVL central frequency). Such a case occurs during experiments in deep waters. This work addresses a theoretical and experimental study on the feasibility of navigating the AUVs using a multi-input Extended Kalman Filter (EKF) integrating proprioceptive measurements (i.e., INS data and speed-over-water observations from DVL) with a set of exteroceptive sensor data, when available. The filter was integrated on-board the CMRE Ocean Explorer Class Version C (OEX-C) AUVs, and tested at sea for the first time in deep water during the NATO exercise Dynamic Mongoose'17 off the South coast of Iceland (June-July 2017).
Validation of a Chinese version of the Medical Outcomes Study Family and Marital Functioning Measures in patients with SLE (2000)

The objective was to validate a Chinese translation of the Medical Outcomes Study Family and Marital Functioning Measures (FFM and MFM) in patients with systemic lupus erythematosus (SLE). Chinese-speaking SLE patients (n = 69) completed a self-administered questionnaire containing the FFM and MFM and assessing demographic and socio-economic status twice within a 2 week period. SLE activity, disease-related damage and quality of life were assessed using the BILAG, SLICC/ACR Damage Index and SF-36 Health Survey, respectively. Scale psychometric properties were assessed through factor analysis, Cronbach's alpha, quantifying test-retest differences and known-groups construct validity. Factor analysis identified 1 factor corresponding to the FFM and 2 factors corresponding to the MFM. Internal consistency for the FFM was excellent (alpha = 0.92) while that for the MFM was acceptable (alpha = 0.62). Mean (s.d.) test-retest differences were 0.06 (1.54) points for the FFM and 0.03 (2.08) points for the MFM. 11 and 10 of 13 a priori hypotheses relating the FFM and MFM, respectively, to demographic, disease and quality of life variables were confirmed, supporting the construct validity of these scales. The Chinese FFM and MFM are valid and reliable measures of family and marital functioning in Chinese-speaking SLE patients, with psychometric properties very similar to the source English version.
Observation of initiation and early growth of small cracks during high-temperature low-cycle fatigue in 304 stainless steel. (1987)

An accurate prediction of fatigue fracture at elevated temperatures depends on the elucidation of the small crack initiation and propagation behavior. Experimental studies on the small cracks, however, have been quite limited. In this study, two types of high-temperature low-cycle fatigue tests, C-P type of a trapezoidal stress waveform with tension hold and P-P type of a high-frequency triangular stress waveform, were conducted by using smooth specimens of 304 stainless steel, and the behavior of initiation and early growth of surface small cracks was observed continuously during the tests with a high-temperature microscope. Furthermore, a detailed study was made by the interrupted tests with the replicas or scanning electron microscopy. The results obtained are summerized as follows. (1) The crack of C-P type fatigue initiates at a grain boundary between two triple points as it opens uniformly and gradually. (2) The crack growth to the adjacent grain boundary in the early stage of C-P type fatigue is caused through the same process as the crack initiation, showing a stepwise and discontinuous manner. (3) The process mentioned at (1) is the process of growth and coalescence of voids on the grain boundary owing to the grain boundary sliding. (4) The crack initiation of P-P type fatigue takes place at the intersection of slip bands and a grain boundary, and most of the cracks propagate along the grain boundaries in the early stage of fatigue. (5) The crack growth rate of P-P type fatigue decreases suddenly when the crack tip comes near to the triple point. (6) The fracture mechanisms of C-P type fatigue and P-P type fatigue are quite alike to that of creep and that of low cycle fatigue at room temperature, respectively.
Interactions of ligands with macromolecules: Rational design of specific inhibitors of aspartic protease of HIV-1 (2002)

We report here molecular modelling and design study of pseudopeptide inhibitors of the HIV-1 aspartic protease as a therapeutic target for AIDS treatment. A QSAR model was developed for computed enzyme–inhibitor complexation Gibbs free energies and observed enzyme inhibition constants for a training set of potent HIV-1 PR inhibitors. Three inhibitor candidates were found to bind the protease more strongly than ritonavir with binding driven also by hydrophobic forces, which enhances their potential use against drug-resistant protease mutants. Linear regression of experimental inhibition constants (pKi = −log10Ki, Ki in [nM]) and calculated enzyme–inhibitor relative complexation Gibbs free energies (ΔΔGcomp, in [kcal · mol−1]) for the training set of known potent PR inhibitors: pKi = 2.4406 − 0.0202 ΔΔGcomp, (n = 11, r = 0.94, σ = 0.49, F = 50.36, α > 95%, Ki prediction range: 0.001–3.0 nM).
Biochemical Characterization of PER-2 and Genetic Environment of <i>bla</i> <sub>PER-2</sub> (2007)

PER-2 was the first detected and the second most prevalent extended-spectrum beta-lactamase in clinical pathogens isolated in Argentina and was also reported only in other South American countries. Citrobacter freundii 33587 was isolated in 1999 in Buenos Aires and was resistant to all tested beta-lactams except cephamycins and carbapenems. The strain produced both plasmid-borne TEM-1 and PER-2 (pI 5.4), which could be transferred by conjugation. By PCR screening, thermal asymmetric interlaced PCR, and DNA sequencing, we detected an ISPa12/IS1387a insertion sequence upstream of bla(PER-2), previously reported as also being associated with bla(PER-1). The presence of similar structures upstream of bla(PER-1) and bla(PER-2) suggests a common origin and mobilization. Compared to bla(PER-1) genes, an additional putative promoter for bla(PER-2) was found. PER-2 kinetic analysis showed its high hydrolysis efficiencies toward both CTX and CAZ (k(cat)/K(m), 0.76 and 0.43 microM(-1).s(-1), respectively).
Histone Deacetylase Inhibitors Sensitize Prostate Cancer Cells to Agents that Produce DNA Double-Strand Breaks by Targeting Ku70 Acetylation (2007)

This study reports a histone deacetylation-independent mechanism whereby histone deacetylase (HDAC) inhibitors sensitize prostate cancer cells to DNA-damaging agents by targeting Ku70 acetylation. Ku70 represents a crucial component of the nonhomologous end joining repair machinery for DNA double-strand breaks (DSB). Our data indicate that pretreatment of prostate cancer cells with HDAC inhibitors (trichostatin A, suberoylanilide hydroxamic acid, MS-275, and OSU-HDAC42) led to increased Ku70 acetylation accompanied by reduced DNA-binding affinity without disrupting the Ku70/Ku80 heterodimer formation. As evidenced by increased Ser(139)-phosphorylated histone H2AX (gammaH2AX), impaired Ku70 function diminished cellular capability to repair DNA DSBs induced by bleomycin, doxorubicin, and etoposide, thereby enhancing their cell-killing effect. This sensitizing effect was most prominent when cells were treated with HDAC inhibitors and DNA-damaging agents sequentially. Mimicking acetylation was done by replacing K282, K317, K331, K338, K539, or K542 with glutamine via site-directed mutagenesis, which combined with computer docking analysis was used to analyze the role of these lysine residues in the interactions of Ku70 with DNA broken ends. Mutagenesis of K282, K338, K539, or K542 suppressed the activity of Ku70 to bind DNA, whereas mutagenesis of K317 or K331 with glutamine had no significant effect. Moreover, overexpression of K282Q or K338Q rendered DU-145 cells more susceptible to the effect of DNA-damaging agents on gammaH2AX formation and cell killing. Overall, the ability of HDAC inhibitors to regulate cellular ability to repair DNA damage by targeting Ku70 acetylation underlies the viability of their combination with DNA-damaging agents as a therapeutic strategy for prostate cancer.