gebhart/patrepeval huggingface dataset:
Differences in ischemia-induced accumulation of amino acids in the cat cortex. (1990)

It is well established that excitatory amino acid neurotransmitters are extensively liberated during ischemia and that they have neurotoxic properties contributing to neuronal injury. To study changes in the liberation of excitatory and other amino acids during cerebral ischemia, we measured their extracellular concentrations and related them to blood flow levels and electrophysiologic activity (electrocorticogram and auditory evoked potentials) before and for up to 2 hours after multiple cerebral vessel occlusion in 14 anesthetized cats. Blood flow levels between 0 and 43 ml/100 g/min were reached. Concentrations of the excitatory amino acid neurotransmitters increased most (aspartate 10-fold, glutamate 30-fold, and gamma-aminobutyric acid 300-fold compared with control values) below a blood flow threshold of 20 ml/100 g/min. The total power of the electrocorticogram and the amplitude of the auditory evoked potentials were affected below the same blood flow threshold. In contrast, concentrations of the nontransmitter amino acids taurine, alanine, asparagine, serine, and glutamine increased 1.5-5-fold as blood flow decreased, while concentrations of the essential amino acids phenylalanine, valine, leucine, and isoleucine did not change during cerebral ischemia. The great increases in concentrations of the excitatory amino acid neurotransmitters below a blood flow threshold close to that for functional disturbance is in accordance with the role of these amino acids in ischemic cell damage. Their release at blood flow levels compatible with cell survival and the increase in their concentrations with severity and duration of cerebral ischemia imply that excitotoxic antagonists may have potential as therapeutic agents.
[(18)F]FluorThanatrace uptake as a marker of PARP1 expression and activity in breast cancer. (2016)

The nuclear enzyme PARP1 plays a central role in sensing DNA damage and facilitating repair. Tumors with BRCA1/2 mutations are highly dependent on PARP1 as an alternative mechanism for DNA repair, and PARP inhibitors generate synthetic lethality in tumors with BRCA mutations, resulting in cell cycle arrest and apoptosis. Zhou et al. recently synthesized an (18)F-labeled PARP1 inhibitor ([(18)F]FluorThanatrace) for PET, and demonstrated high specific tracer uptake in a xenograft model of breast cancer [1]. In the current study, we characterize the level of baseline PARP expression and activity across multiple human breast cancer cell lines, including a BRCA1 mutant line. PARP expression and activity, as measured by levels of PAR and PARP1, is correlated with in vitro [(18)F]FluorThanatrace binding as well as tracer uptake on PET in a xenograft model of breast cancer. Radiotracer uptake in genetically-engineered mouse fibroblasts indicates [(18)F]FluorThanatrace is selective for PARP1 versus other PARP enzymes. This motivates further studies of [(18)F]FluorThanatrace as an in vivo measure of PARP1 expression and activity in patients who would benefit from PARP inhibitor therapy.
Morphology and thermal properties of foams prepared via thermally induced phase separation based on polylactic acid blends (2012)

Blends of poly-l-lactic acid with two different types of polylactic acid with different average molecular weights (50,000 and 175,000 g/mol, respectively) in different proportions (90/10, 80/20 and 70/30) were utilized in order to produce biodegradable and biocompatible scaffolds for soft tissue engineering applications. The scaffolds were produced via thermally induced phase separation starting from ternary systems where dioxane was the solvent and water the non-solvent. Morphology (average pore size and interconnection) was evaluated by scanning electron microscopy. Foams apparent density was also evaluated (porosity ranges from 87% to 92%). Moreover, a differential scanning calorimetry analysis was carried out on the as-obtained scaffold, so as to obtain information about their thermal properties (enthalpy of melting and crystallization). The results showed that is possible to prepare scaffolds of poly-l-lactic acid/polylactic acid via thermally induced phase separation with both polylactic acids and to tune their average pore size (from 40 to 70 µm) by changing some experimental parameters (e.g. demixing temperature). Moreover, the average molecular weight of the polylactic acid in the blend seems to influence the thermally induced phase separation process in terms of demixing temperatures, which resulted higher than pure poly-l-lactic acid for the blends containing the high molecular weight polylactic acid, and lower for the blends containing the low molecular weight polylactic acid. Finally, a decrease in the crystallinity of the foams when increasing polylactic acid content in poly-l-lactic acid/polylactic acid blends was observed, as witnessed by a drop in the enthalpy of melting and crystallization. The results confirm that the morphology and the mechanical properties of the scaffold can be tuned up, starting from poly-l-lactic acid and blending it in different proportions with polylactic acid with different molecular weights.
Tertiary Structure-Based Prediction of How ATRP Initiators React with Proteins (2017)

The growth of polymers from the surface of proteins via controlled radical polymerization depends on the attachment of small molecule initiators to amino acid residues. Our ability to control and harness the power of polymer-based protein engineering is reliant on the accuracy of prediction where and how fast atom transfer radical polymerization (ATRP) initiators will react with a protein surface. We performed a systematic characterization of the reaction between a bromine-functionalized <i>N</i>-hydroxysuccinimide amine-reactive ATRP initiator and the amino groups in lysozyme and chymotrypsin. The tertiary structures of the proteins were used to predict computationally α-amino group and lysine side-chain accessibility and analyze the chemical and structural environment of the amino groups. To predict reactivity from accessibility calculations, a probe radius that resembled the size of the initiator molecule was used. Experimental data showed that the rate of initiator-protein modification at each amine site was related to surface accessibility but not the p<i>K</i><sub>a</sub> of amino groups. Further refinements of the prediction of where the initiator modified the protein and in what sequence were achieved by considering the local environment of each amino group.
Slow to fast alterations in skeletal muscle fibers caused by clenbuterol, a beta 2-receptor agonist (1988)

Chronic treatment of rats with clenbuterol, a beta 2-receptor agonist (8-12 wk), caused hypertrophy of histochemically identified fast- but not slow-twitch fibers within the soleus, while the mean areas of both fiber types were increased in the extensor digitorum longus (EDL). In contrast, treatment with the beta 2-receptor antagonist, butoxamine, reduced fast-twitch fiber size in both muscles. In the solei and to a lesser extent in the EDLs, the ratio of the number of fast- to slow-twitch fibers was increased by clenbuterol, while the opposite was observed with butoxamine. The muscle fiber hypertrophy observed in the EDL was accompanied by parallel increases in maximal tetanic tension and muscle cross-sectional area, while in the solei, progressive increases in rates of force development and relaxation toward values typical of fast-twitch muscles were also observed. Our results suggest a role of beta 2-receptors in regulating muscle fiber type composition as well as growth.
A 2.655 GHz 3-stage Doherty power amplifier using envelope tracking technique (2010)

We demonstrates an optimized design of a highly efficient 3-stage Doherty PA for the 802.16e Mobile world interoperability for microwave access(WiMAX) application at 2.655-GHz. The `3-stage' Doherty PA is the most efficient architecture among the various Doherty PAs for a high peak to average power ratio(PAPR) signal. However, due to the low quiescent bias point of the peaking PA, it has an improper load modulation problem, which causes over saturated operation of the carrier PA and insufficient peak power. We have solved the problem using a gate envelope tracking(ET) technique. Using the ADS and Matlab simulations, the behavior of the 3-stage Doherty PA employing the ET technique is presented. For the WiMAX signal with a 7.8 ~ 8.5 dB PAPR and 20-MHz instantaneous bandwidth, the measured efficiency of the proposed 3-stage Doherty PA has been maintained 56.7% at an average output power of 43.3 dBm, a 7.2 dB backed-off output power from peak output power level. These experimental results clearly show that the 3-stage Doherty with ET technique has a superior efficiency with high peak power. The PAs accompanied with the DPD are very good candidates for the highly efficient and linear base-station transmitter.
Effects of gamma-interferon on human neutrophils: protection from deterioration on storage (1992)

Human polymorphonuclear leukocytes (PMN) preincubated overnight with 100 U/mL gamma-interferon (IFN-gamma) had an increased metabolic response, as measured by iodination and/or superoxide production, to stimulation by tumor necrosis factor (TNF), granulocyte-macrophage colony-stimulating factor (GM-CSF), formylmethionyl-leucyl-phenylalanine (FMLP), opsonized zymosan, and lipopolysaccharide (LPS), as compared with cells comparably preincubated in the absence of IFN-gamma. The decline in the staphylocidal activity of the stored PMN was also prevented in part by IFN-gamma, as was the depressed adherence of PMN stimulated with phorbol myristate acetate (PMA), FMLP, TNF, GM-CSF, and LPS. This protective effect of IFN-gamma on PMN function was associated with the prolonged surface expression of the complement receptor three (CR3) alpha-chain (CD11b), CR3 beta-chain (CD18), FcRII (CD32), and FcRIII (CD16), and the appearance of surface FcRI (CD64). The polymerase chain reaction (PCR) was used to amplify neutrophil RNA-derived cDNA recognized by synthetic oliogonucleotides designed from published nucleotide sequences for specific proteins. Using this procedure, mRNA for gp91-phox, p67-phox, p47-phox, CD64, two forms of CD32, CD16, CD11b, CD18, and actin were found to be depressed after overnight storage of neutrophils, and this decrease in steady-state mRNA levels was in part or totally prevented by IFN-gamma. CD64 and gp91-phox mRNA were generally increased by IFN-gamma to a level greater than that of freshly isolated neutrophils. Northern analysis of CD64 and p47 phox mRNAs confirmed the findings with the PCR method. These findings suggest that storage of PMN in a functionally active state is favored by the presence of IFN-gamma.
Introduction: The New American Studies (1991)

The essays in this collection represent the work of a new generation within American studies, and they define a new idea of what it might mean to do American studies and how one would go about doing it.They also represent the rich diversity of explanations and materials in the study of American culture.Films and photographs, Supreme Court decisions and industrial manuals, educational and domestic theory, the popular culture of Horatio Alger and the standard genres of domestic fiction: a culture in its full institutional and individual variety is here in play.At the same time, because these essays have been drawn from the journal Representations they do not reach out to every recent style or topic of analysis.To take one limitation, Whitman is the only poet who plays a central part here.One way to characterize this new generation of American studies would be to say that interest has passed from myth to rhetorics.Myth in this perhaps too simple formula is always singular, rhetorics always plural.Myth is a fixed, satisfying, and stable story used again and again to normalize our account of social life.By means of myth novelty is tamed by being seen as the repetition or, at most, the variation, of a known and valued pattern.Even where actual historical situations are found to fall short of myth or to lie in its aftermath, the myth tames the variety of historical experience, giving it familiarity while using it to reaffirm the culture's long-standing interpretation of itself.Rhetoric, on the other hand, is a tactic within the open questions of culture.It reveals interests and exclusions.To look at rhetorics is to look at the action potential of language and images, not just their power or contrivance to move an audience but also the location of words, formulas, images, and ideological units of meaning within politics.Rhetoric is the place where language is engaged in cultural work, and such work can be done on, with, or in spite of one or another social group.Rhetorics are plural because they are part of what is uncertain or potential in culture.They are the servants of one or another politics of experience.Where there is nothing openly contested, no cultural work to be done, we do not find the simplification into one and only one rhetoric.Instead we find the absence of the particular inflammation and repetition that rhetoric always marks.We find not rhetoric, but the ceremonial contentment of myth.Rhetorics are also distinct from ideology.In the term ideology we rightly hear a combination of cal-
A neural network approach to data predistortion with memory in digital radio systems (2002)

The authors present an algorithm to determine the coefficients of a general data-predistorter with memory for compensation of high-power amplifier (HPA) nonlinearities in digital microwave radio systems. This technique is based on modeling the predistorter-modulator-HPA system as a neural network with memory. It is shown that, by extending the optimization algorithm of back-propagation to complex signals and with neurons modeled as finite-impulse-response (FIR) filters, the proposed algorithm determines automatically the predistorter with the objective that the overall transmitter behaves as a linear system with a prescribed pulse shape. The novelty with respect to previous techniques is that in the present scheme a control on the spectrum of the signal after the HPA is exercised. This minimizes the interference between adjacent channels. The algorithm has been tested successfully in several radio systems employing quadrature amplitude modulation (QAM) signal formats, and some examples of its application are reported.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Arsenic Pileup at the SiO2 / Si Interface (1995)

Sheet resistance measurements and a Rutherford backscattering spectroscopy analysis show arsenic piles up at the interface between and single‐crystalline silicon. The arsenic piles up mainly in the and can be removed by hydrofluoric acid. Less arsenic piles up than does phosphorus. These results are qualitatively discussed in terms of stress reduction at the interface.
The treatment of postanaesthetic shivering: a double blind comparison between alfentanil and pethidine (1995)

It has been postulated that pethidine may mediate its effects on postanaesthetic shivering (PAS) via kappa-opioid receptors. However, clinical evidence indicates that alfentanil, a pure mu-agonist, may also have beneficial effects on PAS. In order to assess whether opioid effects on PAS are effected via kappa receptors, fifty-one patients were randomised to receive alfentanil 250 micrograms (n = 18), pethidine 25 mg (n = 18) or placebo (n = 15) on a double-blind basis for the treatment of established postanaesthesia shivering (PAS). Both drugs proved significantly better in treating PAS than placebo (P < 0.005). Following treatment, blood pressure fell and oxygen saturation increased in patients in the two treatment groups when compared with the control group (P < 0.05). There was a highly significant incidence of reshivering in the alfentanil treated group (P < 0.005). In conclusion, the high incidence of reshivering indicates that alfentanil is unlikely to supercede pethidine in the treatment of PAS, but its initial success rate implies that pethidine's anti-shivering effect is unlikely to be mediated via kappa-opioid receptors.
On P-simple points (1995)

A simple point of an object is a point whose removal does not change the topology. However, the simultaneous deletion of simple points may change the topology. A popular way for overcoming this problem is to use a directional strategy. This method has good properties in two-dimensional discrete spaces but it does not work in three-dimensions. Through the notion of P-simple point we propose a general strategy for removing points in parallel without altering the topology of a 3D space. We also propose a characterization of P-simple points which may be implemented with a linear time complexity
Bcr-Abl with an SH3 Deletion Retains the Ability To Induce a Myeloproliferative Disease in Mice, yet c-Abl Activated by an SH3 Deletion Induces Only Lymphoid Malignancy (1999)

The bcr-abl oncogene plays a critical role in the pathogenesis of chronic myelogenous leukemia (CML). The fusion of Bcr sequences to Abl constitutively activates the Abl protein tyrosine kinase. We have recently shown that expression of Bcr-Abl in bone marrow cells by retroviral transduction efficiently induces in mice a myeloproliferative disease resembling human CML and that Abl kinase activity is essential for Bcr-Abl to induce a CML-like myeloproliferative disease. However, it is not known if activation of the Abl kinase alone is sufficient to induce a myeloproliferative disease. In this study, we examined the role of the Abl SH3 domain of Bcr-Abl in induction of myeloproliferative disease and tested whether c-Abl activated by SH3 deletion can induce a CML-like disease. We found that Bcr-Abl with an Abl SH3 deletion still induced a CML-like disease in mice. In contrast, c-Abl activated by SH3 deletion induced only lymphoid malignancies in mice and did not stimulate the growth of myeloid colonies from 5-fluorouracil-treated bone marrow cells in vitro. These results indicate that Bcr sequences in Bcr-Abl play additional roles in inducing myeloproliferative disease beyond simply activating the Abl kinase domain and that functions of the Abl SH3 domain are either not required or redundant in Bcr-Abl-induced myeloproliferative disease. The results also suggest that the type of hematological neoplasm induced by an abl oncogene is influenced not only by what type of hematopoietic cells the oncogene is targeted into but also by the intrinsic oncogenic properties of the particular abl oncogene. In addition, we found that DeltaSH3 c-Abl induced less activation of Akt and STAT5 than did Bcr-Abl, suggesting that activation of these pathways plays a critical role in inducing a CML-like disease.
Towards Realistic Implementations of a Majorana Surface Code (2016)

Surface codes have emerged as promising candidates for quantum information processing. Building on the previous idea to realize the physical qubits of such systems in terms of Majorana bound states supported by topological semiconductor nanowires, we show that the basic code operations, namely projective stabilizer measurements and qubit manipulations, can be implemented by conventional tunnel conductance probes and charge pumping via single-electron transistors, respectively. The simplicity of the access scheme suggests that a functional code might be in close experimental reach.
[ <sup>11</sup> C] <i>(R)-PK11195 positron emission tomography imaging of activated microglia in vivo in Rasmussen’s encephalitis</i> (1999)

This study was designed to explore the feasibility of PET using [11C](R)-PK11195 as an in vivo marker of activated microglia/brain macrophages for the assessment of neuroinflammation in Rasmussen's encephalitis (RE). [11C](R)-PK11195 PET was carried out in four normal subjects, two patients with histologically confirmed RE, and three patients with clinically stable hippocampal sclerosis and low seizure frequency. Binding potential maps showing specific binding of [11C](R)-PK11195 were generated for each subject. Regional binding potential values were calculated for anatomically defined regions of interest after coregistration to and spatial transformation into the subjects' own MRI. In one patient with RE who underwent hemispherectomy, the resected, paraffin-embedded brain tissue was stained with an antibody (CR3/43) that labels activated human microglia. Whereas specific binding of [11C](R)-PK11195 in clinically stable hippocampal sclerosis was similar to that in normal brain, patients with RE showed a focal and diffuse increase in binding throughout the affected hemisphere. In RE, [11C](R)-PK11195 PET can reveal in vivo the characteristic, unilateral pattern known from postmortem neuropathologic study. PET imaging of activated microglia/brain macrophages offers a tool for investigation of a range of brain diseases where neuroinflammation is a component and in which conventional MRI does not unequivocally indicate an inflammatory tissue reaction. [11C](R)-PK11195 PET may help in the choice of appropriate biopsy sites and, further, may allow assessment of the efficacy of antiinflammatory disease-modifying treatment.
Endoleaks after Endovascular Abdominal Aortic Aneurysm Repair: Detection with Dual-Energy Dual-Source CT (2008)

Purpose: To assess the diagnostic performance of dual-energy dual-source computed tomography (CT) in the detection of endoleaks after endovascular abdominal aortic aneurysm (AAA) repair. Materials and Methods: This study was local ethics board approved, and written informed consent was obtained from all patients. One hundred eighteen patients (21 women, 97 men; mean age, 74 years ± 8 [standard deviation]) underwent follow-up dual-energy dual-source CT during the nonenhanced, arterial, and delayed phases after AAA repair. Delayed phase CT images were acquired in the dual-energy mode for reconstruction of virtual nonenhanced images. Two blinded and independent readers evaluated the data for the presence or absence of endoleaks during three reading sessions: Standard nonenhanced, arterial phase, and delayed phase images were read during session A; virtual nonenhanced, arterial phase, and delayed phase images, during session B; and virtual nonenhanced and delayed phase images, during session C. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated, with the session A image data set as the reference standard. Radiation dose parameters were estimated. Results: Reading session A revealed that 52 (44%) of 118 patients had endoleaks. Overall sensitivity, specificity, NPV, and PPV for CT endoleak detection during sessions B and C were identical: 100%, 97%, 100%, and 96%, respectively. The accuracy of the session B and session C readings was not significantly different from that of the session A reading (P = .50). The effective radiation dose in the image acquisition protocol involving one dual-energy scan was significantly (P < .001) lower than the effective doses in the protocols involving standard triple-phase scanning (mean difference, 61%) and standard nonenhanced and delayed phase scanning (mean difference, 41%). Conclusion: Compared with standard protocols, one dual-energy dual-source CT scan performed during the delayed phase with reconstruction of virtual nonenhanced images enables detection of endoleaks after endovascular AAA repair with high accuracy and a considerably lower radiation dose. © RSNA, 2008
Iridium‐Catalyzed Asymmetric Allylic Substitutions. (2007)

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