gebhart/patrepeval huggingface dataset:
Initiation of cationic polymerization of n‐butyl vinyl ether by stable cation radicals of substituted phenothiazines (1994)

Abstract 3,7‐Diethyl‐ 10‐phenylphenothiazine (DEPPT), a phenothiazine derivative whose 3,7‐ and 10‐positions are blocked, was synthesized. Potentiostatic electrolysis of DEPPT in acetonitrile (ACN) in the presence of 0.1 M of LiClO 4 at 0.7 V (vs. Ag/Ag/Cl) yielded the stable cation radical of DEPPT (DEPPT +· ) which was characterized by cyclic voltammetry, UV‐visible spectroscopy, and ESR spectrometry. Stable cation radicals of 10‐phenylphenothiazine and 3,7‐diethyl‐10‐methylphenothiazine were also prepared. The cationic polymerization of n ‐butyl vinyl ether was initiated by these cation radicals, including DEPPT ·+ . The electron transfer mechanism for the initiation step, which we proposed previously, was supported by the fact that DEPPT ·+ was capable of initiating the polymerization; dimerization of DEPPT ·+ by releasing protons is precluded because 3,7‐ and 10‐positions are all blocked. © 1994 John Wiley &amp; Sons, Inc.
A Meldrum's Acid Based Multicomponent Synthesis of N‐Fmoc‐isoxazolidin‐5‐ones: Entry to N‐Fmoc‐β‐amino Acids (2017)

A multicomponent Knoevenagel–aza‐Michael cyclocondensation (KaMC) reaction starting from Meldrum's acid has been developed with base‐sensitive N ‐Fmoc‐hydroxylamine. The reaction takes place under very mild basic conditions, providing a straightforward synthetic route to various unprecedented N ‐Fmoc‐isoxazolidin‐5‐ones. Subsequent chemoselective reductive cleavage of the N–O bond in the presence of Zn/AcOH allowed a short synthesis of the corresponding N ‐Fmoc‐β‐amino acids.
Reversibly Assembled Cellular Composite Materials (2013)

We introduce composite materials made by reversibly assembling a three-dimensional lattice of mass-produced carbon fiber-reinforced polymer composite parts with integrated mechanical interlocking connections. The resulting cellular composite materials can respond as an elastic solid with an extremely large measured modulus for an ultralight material (12.3 megapascals at a density of 7.2 milligrams per cubic centimeter). These materials offer a hierarchical decomposition in modeling, with bulk properties that can be predicted from component measurements and deformation modes that can be determined by the placement of part types. Because site locations are locally constrained, structures can be produced in a relative assembly process that merges desirable features of fiber composites, cellular materials, and additive manufacturing.
PULSATION PERIOD VARIATIONS IN THE RRc LYRAE STAR KIC 5520878 (2014)

Learned et al. proposed that a sufficiently advanced extra-terrestrial civilization may tickle Cepheid and RR Lyrae variable stars with a neutrino beam at the right time, thus causing them to trigger early and jogging the otherwise very regular phase of their expansion and contraction. This would turn these stars into beacons to transmit information throughout the galaxy and beyond. The idea is to search for signs of phase modulation (in the regime of short pulse duration) and patterns, which could be indicative of intentional, omnidirectional signaling. We have performed such a search among variable stars using photometric data from the Kepler space telescope. In the RRc Lyrae star KIC 5520878, we have found two such regimes of long and short pulse durations. The sequence of period lengths, expressed as time series data, is strongly autocorrelated, with correlation coefficients of prime numbers being significantly higher (p = 99.8%). Our analysis of this candidate star shows that the prime number oddity originates from two simultaneous pulsation periods and is likely of natural origin. Simple physical models elucidate the frequency content and asymmetries of the KIC 5520878 light curve. Despite this SETI null result, we encourage testing of other archival and future time-series photometry for signs of modulated stars. This can be done as a by-product to the standard analysis, and can even be partly automated.
Plant Haemoglobins, Nitric Oxide and Hypoxic Stress (2003)

It is now known that there are several classes of haemoglobins in plants. A specialized class of haemoglobins, symbiotic haemoglobins, were discovered 62 years ago and are found only in nodules of plants capable of symbiotic nitrogen fixation. Plant haemoglobins, with properties distinct from symbiotic haemoglobins were discovered 18 years ago and are now believed to exist throughout the plant kingdom. They are expressed in different organs and tissues of both dicot and monocot plants. They are induced by hypoxic stress and by oversupply of certain nutrients. Most recently, truncated haemoglobins have been shown to also exist in plants. While hypoxic stress-induced haemoglobins are widespread in the plant kingdom, their function has not been elucidated. This review discusses the recent findings regarding the function of these haemoglobins in relation to adaptation to hypoxia in plants. We propose that nitric oxide is an important metabolite in hypoxic plant cells and that at least one of the functions of hypoxic stress-induced haemoglobins is to modulate nitric oxide levels in the cell.
A Major Triterpenoid Saponin from Gypsophila oldhamiana (2007)

A new saponin, gypoldoside A (1), was isolated from the roots of Gypsophila oldhamiana. On the basis of in-depth NMR-spectroscopic and mass-spectrometric analysis, in combination with chemical evidence, its structure was established as 3-O-{beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl}quillaic acid 28-[alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranosyl] ester. Compound 1 was found to be highly active against three different human cancer cell lines, with IC50 values in the low micromolar range.
Superficial temporal artery to middle cerebral artery anastomosis (1979)

Fluorescein angiography and xenon-133 (133Xe) clearance studies were performed during surgery on 15 patients who were undergoing superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis. Fourteen patients had occlusive disease of the internal carotid artery (ICA), and one patient had severe stenosis of the MCA. Before anastomosis, fluorescein angiography showed slow filling of the MCA branches through collateral channels. Focal areas of impaired microcirculatory filling and washout were seen in the territory of severely sclerotic cortical arteries. The findings of preanastomotic 133Xe clearance studies were variable and a uniform pattern of regional cerebral blood flow (rCBF) changes was not defined. In 55% of the patients, rCBF was reduced to 25 ml/100 gm/min or less at one or more detector sites. Fluorescein angiography provided an immediate assessment of anastomotic patency and clearly displayed the distribution of blood entering the epicerebral circulation through the STA. In 67% of patients, multiple MCA cortical branches filled with fluorescein, whereas in 33% filling was restricted to the receptor artery territory. An immediate, substantial (greater than or equal to 15 ml/100 gm/min) increase in rCBF was demonstrated in 73% of patients after anastomosis. The rCBF changes were consistently better in patients with donor and receptor arteries greater than 1 mm in diameter. Redistribution of collateral input acted to increase rCBF in areas distant from the anastomotic site. Some improvement in fluorescein circulation and rCBF also was seen in cortex supplied by sclerotic MCA branches.
Mapping the Subsite Preferences of Protein Tyrosine Phosphatase PTP-1B Using Combinatorial Chemistry Approaches (1998)

Protein tyrosine phosphatases (PTPases) are important regulators of signal transduction systems, but the specificity of their action is largely unexplored. We have approached this problem by attempting to map the subsite preferences of these enzymes using combinatorial chemistry approaches. Protein-tyrosine peptidomimetics containing nonhydrolyzable phosphotyrosine analogues bind to PTPases with high affinity and act as competitive inhibitors of phosphatase activity. Human PTP-1B, a PTPase implicated to play an important role in the regulation of growth factor signal transduction pathways, was used to screen a synthetic combinatorial library containing malonyltyrosine as a phosphotyrosine mimic. Using two cross-validating combinatorial chemistry screening approaches, one using an iterative method and the other employing library affinity selection-mass spectrometric detection, peptides with high affinity for PTP-1B were identified and subsite preferences were detailed by quantitatively comparing residues of different character. Consistent with previous observations, acidic residues were preferred in subsites X-3 and X-2. In contrast, aromatic substitutions were clearly preferred at the X-1 subsite. This information supports the concept that this class of enzymes may have high substrate specificity as dictated by the sequence proximal to the phosphorylation site. The results are discussed with regards to the use of combinatorial techniques in order to elucidate the interplay between enzyme subsites.
Use of ambulance dispatch calls for surveillance of severe acute respiratory infections? (2019)

ObjectiveWe aim to assess whether influenza circulation, as measured through influenza-like-illness (ILI) in primary care, is reflected in ambulance dispatch (AD) calls.IntroductionSurveillance of severe influenza infections is lacking in the Netherlands. Ambulance dispatch (AD) data may provide information about severity of the influenza epidemic and its burden on emergency services.The current gold standard, primary care-based surveillance of influenza-like-illness (ILI), mainly captures mild to moderate influenza cases, and does not provide adequate information on severe disease.Monitoring the severity of the annual epidemic, particularly among groups most at risk of complications, is of importance for the planning of health services and the public health response.MethodsWe analysed all calls from four ambulance dispatch centers serving 4.3 million people in the Netherlands, between January 2014 and December 2016. The main complaint and urgency level is recorded during triage; those possibly caused by respiratory infections were grouped as respiratory syndrome calls (RSC). We modelled the proportion of all RSC calls against the weekly ILI incidence (we allowed up to 4-week lags and leads), from sentinel primary-care surveillance. We used binomial regression with identity link to obtain differences in proportions. We built separate models by age group, urgency level and time of day. We tested heterogeneity of effects by season.ResultsWe included 289,307 calls; 6.7% were RSC. Overall, proportion of RSC increased by 0.114 percentage points for each increase of 1/10,000 population in ILI incidence. In our study population, this translated into 550 ambulance calls attributable to influenza (as measured by ILI) per year. Association was stronger in the models including only out-of-office hours, children (&lt;15 years) and highest urgency level calls. In the latter two, the effect varied by season. RSC was best associated with ILI from the previous 1-3 weeks in all models, except in children where RSC preceded ILI by 1 week.ConclusionsOur results demonstrate the potential usefulness of ambulance dispatch data to complement existing influenza surveillance by providing information on the volume and timing of severe cases attributable to influenza within the yearly epidemics.
Low-Temperature Sintering of Nanoscale Silver Paste for Power Chip Attachment (2008)

European electronic manufacturers, particularly those in power electronics, are aggressively implementing a silver sintering technology for interconnecting semiconductor chips. It has been shown that power modules with sintered chip-attachment have 3x better performance, 5x better reliability, and higher chip junction temperature up to 175°C. However, because of the use of commercial thick-film silver pastes in the process, a serious drawback of the sintering technology is the need of a high quasi-static pressure (~ 40 MPa) to lower the sintering temperature to about 250°C. Using the large pressure complicates the manufacturing process and places critical demands on substrate flatness and chip thickness. In this paper, we describe a strategy of using nanoparticles of silver to lower its sintering temperature without any applied pressure. From the science of sintering, driving force for densification of a particle compact increases with decreasing particle size, thus the densification rate-a product of thermodynamic driving force and kinetics-could still be high at low temperatures even with low atomic diffusion rate. We formulated a uniform silver paste containing 30 to 50 nm silver particles. The sintered attachment at temperatures below 275°C without applying any pressure had a density of about 80% and a uniform distribution of micron-sized pores. The sintered chip-attachment had die-shear strength over 20 MPa, and it showed little change after aging at 300oC for 400 hours. Temperature-cycling tests have been performed and results are presented in this paper. Based on the results, we believe that the nanoscale silver paste can enable a quick adaptation of the low-temperature silver-joining technology for manufacturing electronics products.
Building performance monitoring: from in-situ measurement to regression-based approaches (2019)

Abstract Simple and robust data analysis methodologies are crucial to learn insights from measured data and reduce the performance gap in building stock. For this reason, continuous performance monitoring should become a more diffuse practice in order to improve our design and operation strategies for the future. The research presented aims to highlight potential links between experimental approaches for test-facilities and methods and tools used for continuous performance monitoring, at the state of the art. In particular, we explore the relation between ISO 9869:2014 method for in-situ measurement of thermal transmittance ( U ) and regression-based monitoring approaches, such as co-heating test and energy signature, for heat load coefficient ( HLC ) and solar aperture ( gA ) estimation. In particular, we highlight the robustness and scalability of these monitoring techniques, considering relevant issues in current integrated engineer design perspective. These issues include, among others, the necessity of limiting the number of a sensors to be installed in buildings, the possibility of employing both experimental and real operation data and, finally, the possibility to automate and perform monitoring at multiple scales, from single components, to individual buildings, to building stock and cities.
Femtosecond near-IR optical parametric oscillator with efficient intracavity generation of visible light (2002)

We present an experimental and a theoretical analysis of the operation characteristics of a femtosecond optical parametric oscillator (OPO) based on periodically poled LiNbO3 (PPLN). It provides bright visible pulses through second-harmonic generation (SHG) of the signal and sum-frequency generation (SFG) between the signal and the pump, simultaneously with the parametric oscillation in the near IR. Using a duty cycle of the poling period of approximately 56%, we achieved strong enhancement of even-order quasi-phase-matched (QPM) SHG and SFG, whereas the reduction in the efficiencies of odd-order QPM processes is negligible. Femtosecond pulses with output powers of up to 14 mW in the blue, 12 mW in the green, and 18 mW in the red were obtained for a pump power of only 480 mW. The tuning ranges extended from 460 nm to 500 nm and from 520 nm to 660 nm for SFG between the pump and signal and SHG of the signal, respectively, with at least 2-mW output power. Our work demonstrates that proper choice of the duty cycle of the poling period allows exploitation of higher-order QPM for intracavity SHG and SFG processes in PPLN OPOs.
Serum Amyloid Protein A 1 (hSAA1) Is Overexpressed in Myelodysplastic Syndromes and Potentially Mediates Toll-Like Receptor 2 Innate Immunity Signaling in CD34+ Hematopoietic Stem Cells (2012)

Abstract Abstract 1703 Myelodysplastic syndromes (MDS) are a group of myeloid malignancies that originate from bone marrow hematopoietic stem/ progenitor cells (HSC). We have previously reported that deregulation of Toll-like Receptor (TLR) 2 mediated innate immunity signaling contributes to the pathogenesis of MDS through its impact on HSC. Several amyloid family peptides have been reported to be endogenous TLR2 agonists, including Ab-42 and the serum amyloid protein A (SAA1). To further dissect the role of this TLR2 centered molecular signaling in MDS, we characterized these amyloid peptides in MDS. Elisa assays indicated that the concentration of SAA1 protein in bone marrow plasma of MDS patients (N=17) was 3 fold higher (p-value 0.01) compared to normal controls, whereas in the same patient cohort the concentration of Ab-42 in MDS bone marrow plasma was elevated by ∼ 1.5 fold. We then examined expression of SAA1 in bone marrow CD34+ cells of MDS. RT-PCR results indicated that SAA1 RNA level was increased by 18 fold in MDS CD34+ cells compared to control (N=64, p-value 0.0001). While it is known that expression of SAA1 is highly sensitive to acute and chronic inflammation and can be regulated by multiple inflammatory cytokines such as IL-6 and IL-8, its regulation by TLR2 mediated signal in HSC is unknown. To examine the impact of TLR2 signal on SAA1 expression, we profiled RNA expression in an OCI-AML3 cell line that stably expresses the shRNA against TLR2. Microarray analysis indicated that in TLR2 shRNA expressing cells, RNA level of SAA1 decreased by ∼50%. Similar decrease of SAA1 RNA was also detected when primary CD34+ cells isolated from the bone marrow of MDS patients (N=4) were treated with retroviral mediated TLR2 shRNA. These results suggest that TLR2 deregulation may contribute to the overexpression SAA1 in MDS CD34+ cells. Further, we examined whether elevated bone marrow SAA1 level could affect HSC function. We treated in vitro cultured bone marrow CD34+ cells with a recombinant 105 amino acid SAA1 peptide and then analyzed its impact on hematopoietic colony formation in methylcellulose-medium. Results derived from four CD34+ HSC samples indicated that 1mg/ml SAA1 peptide led to a 16% decrease of hematopoietic colony numbers (p-value 0.02). This result suggests that SAA1 can negatively affect the hematopoietic capacity of HSC. Taken together, this study suggests that SAA1 may be part of the deregulated TLR2 mediated innate immunity signaling network that contributes to MDS pathogenesis. Previous studies have indicated that SAA level was elevated in HSC of the mice with telomere dysfunction (Sahin et al. Nature 2011). Therefore, we hypothesize that SAA is involved in the pathogenesis of MDS during ageing. Further molecular analysis of the role of SAA1, and its clinical impact (that is being analyzed), during ageing and MDS require further investigation. Disclosures: No relevant conflicts of interest to declare.
Gold‐Induced Structural Switch of Cys34 in Albumin: Comparison ofAuranofin With Aurothiomalate (1994)

Albumin, a single-chain protein of ca. 580 amino acids (66.5 kDa), is the major protein in blood serum with a concentration of ca. 0.63 mM. The protein .consists of three largely a-helical structurally-similar domains, each of which contains two sub-domains [1]. It plays a central role in the molecular
Correlation of pre-CAR CD19 expression with responses and relapses after CAR T cell therapy. (2018)

3051 Background: Chimeric antigen receptor (CAR) T cells targeting CD19 have shown excellent responses in patients with relapsed/refractory B-ALL. However, a subset of patients either do not respond or relapse after CAR T cell therapy, the causes of which are unclear. The use of CD19-directed therapy has increased the incidence of CD19 dim or CD19 negative B-ALL. We assessed whether pre-treatment CD19 expression level or prior targeted therapy impacts response to CAR therapy. Methods: Cases of B-ALL treated with CAR therapy from 2012-2017 at Children’s Hospital of Philadelphia were evaluated. CD19 in blasts was classified as dim, normal or bright compared to normal B cells by flow cytometry. CD19 expression and immunophenotype of blasts pre and post-CAR therapy were correlated with responses to CAR T cell therapy. Failure to reach an MRD-negative remission was considered as non-response. Presence of aberrant blasts ( > 0.01%)at any time point after remission was considered as relapsed disease. Results: 150 cases treated with CAR therapy were evaluated of which 10 were non-response (NON), 20 were CD19 positive relapses (CD19PR) and 33 were CD19 negative relapses (CD19NR). 15 patients received prior CD19 targeted therapy. Rate of responses and relapses in CD19dim B-ALL were not significantly different from the CD19 normal/bright group. However, prior CD19-targeted therapy was associated with a significantly higher rate (60%; p = 0.014) of NON and CD19NR compared to 25% in patients who did not receive any prior CD19 targeted therapy. Immunophenotype of CD19PR were identical to that of pre-therapy disease in 85% of cases, consistent with loss of CAR T cells as the etiology of those relapses. Blasts from CD19NR patients did not show any CD19-negative events by flow prior to CAR T cell therapy in 75% of cases suggesting that CD19-negative blasts may be de novo events. Conclusions: CAR T cell therapy is effective in B-ALL with dim CD19 expression. Prior targeted therapy is associated with increased non-response and relapse, likely due to CD19 escape. CD19PR after CAR T cell therapy are due to early loss of CAR T cells while CD19NR are likely due to expansion of de novo CD19-negative B lymphoblasts under treatment pressure.
Electron paramagnetic resonance saturation characteristics of pristine and doped polyacetylenes (1982)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectron paramagnetic resonance saturation characteristics of pristine and doped polyacetylenesJames C. W. Chien, Gary E. Wnek, Frank E. Karasz, John M. Warakomski, L. Charles Dickinson, Alan J. Heeger, and Alan G. MacDiarmidCite this: Macromolecules 1982, 15, 2, 614–621Publication Date (Print):March 1, 1982Publication History Published online1 May 2002Published inissue 1 March 1982https://pubs.acs.org/doi/10.1021/ma00230a079https://doi.org/10.1021/ma00230a079research-articleACS PublicationsRequest reuse permissionsArticle Views181Altmetric-Citations44LEARN 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