gebhart/patrepeval huggingface dataset:
4. The Implicitly Restarted Arnoldi Method (1998)

This chapter presents an overview of the theory of Krylov subspace projection and the underlying algorithms implemented in ARPACK. The basic implicitly restarted Arnoldi method (IRAM) is quite simple in structure and is very closely related to the implicitly shifted QR-algorithm for dense problems. This discussion is intended to give a broad overview of the theory and to develop a high-level description of the algorithms. Specific implementation details concerned with efficiency and numerical stability are treated in Chapter 5. The remainder of this chapter will develop enough background to understand the origins, motivation, and expected behavior of this algorithm. The discussion begins with a very brief review of the structure of the algebraic eigenvalue problem and some basic numerical methods that either influence or play a direct role in the IRAM. Overcoming the basic disadvantages of the simple power method motivates the introduction of Krylov subspaces along with the important projection idea and the related approximation properties. The Lanczos/Arnoldi factorization is introduced as a concrete way to construct an orthogonal basis for a Krylov subspace and provides a means to implement the projection numerically. Implicit restarting is introduced as an efficient way to overcome the often intractable storage and computational requirements in the original Lanczos/Arnoldi method. This new technique turns out to be a truncated form of the implicitly shifted QR algorithm, and hence implementation issues and ultimate behavior are closely tied to that well-understood method. Because of its reduced storage and computational requirements, the technique is suitable for large-scale eigenvalue problems. Implicit restarting provides a means to approximate a few eigenvalues with user-specified properties in space proportional to n · k, where k is the number of eigenvalues sought. Generalized eigenvalue problems are discussed in some detail. They arise naturally in PDE applications, and they have a number of subtleties with respect to numerically stable implementation of spectral transformations.
Regioselective synthesis of [60]fullerene η<sup>5</sup>-indenide R<sub>3</sub>C<sub>60</sub><sup>−</sup>and η<sup>5</sup>-cyclopentadienide R<sub>5</sub>C<sub>60</sub><sup>−</sup>bearing different R groups (2003)

Treatment of a 1,7-diorgano[60]fullerene with Grignard reagents or organocopper reagents affords a [60]fullerene indenide or a [60]fullerene cyclopentadienide regioselectively in good to excellent yields. These reactions gave an insight into the reaction mechanism of the organocopper penta-addition reaction of [60]fullerene, giving [60]fullerene cyclopentadienide in quantitative yield.
Steroidal Hormone Analogs. IX. Bisdehydrodoisynolic Acid Analogs Possessing the 1,2,3,4-Tetrahydrobenz[f]isoquinoline Nucleus<sup>1</sup> (1961)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSteroidal Hormone Analogs. IX. Bisdehydrodoisynolic Acid Analogs Possessing the 1,2,3,4-Tetrahydrobenz[f]isoquinoline Nucleus1NORMAN A. NELSON and RICHARD S. P. HSICite this: J. Org. Chem. 1961, 26, 9, 3086–3090Publication Date (Print):September 1, 1961Publication History Published online1 May 2002Published inissue 1 September 1961https://pubs.acs.org/doi/10.1021/jo01067a010https://doi.org/10.1021/jo01067a010research-articleACS PublicationsRequest reuse permissionsArticle Views41Altmetric-Citations1LEARN 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
Proton‐conducting polymers based on benzimidazoles and sulfonated benzimidazoles (2002)

Abstract A sulfonated derivative of polybenzimidazole is reported, and its properties are analyzed in comparison with related polybenzimidazole proton‐conducting materials. Poly(2,5‐benzimidazole), poly( m ‐phenylenebenzobisimidazole), and poly[ m ‐(5‐sulfo)‐phenylenebenzobisimidazole] were prepared by condensation of the corresponding monomers in polyphosphoric acid. Several adducts of these polymers with phosphoric acid were prepared. The resulting materials were characterized by chemical analysis, Fourier transform infrared spectroscopy, and thermogravimetric analysis; also, the dc conductivity of doped and undoped derivatives was measured. Similar to what has been observed for the commercial polybenzimidazole polymer (also examined here for comparison), the title polymers exhibit high thermal stability. Furthermore, their doping with phosphoric acid leads to a significant increase in conductivity from less than 10 −11 Scm −1 for the undoped polymers to 10 −4 Scm −1 (both at room temperature) for their acid‐loaded derivatives. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3703–3710, 2002
Design of an 128-point FFT processor for OFDM applications (2002)

Important issues in designing ASICs are short design time, flexibility, reuse of building blocks, and reliability. These factors can be met by using automatic design tools and standard-cell design. The major drawback with this approach is the attainable circuit performance. In this paper we present an efficient design approach which combines the short design time and flexibility of the standard-cell approach and the high performance of the unconstrained cell layout style. A 128-point FFT/IFFT chip aimed at OFDM applications has successfully been designed using this approach. Further, a modular architecture is proposed that is scalable with respect to the throughput requirements. The throughput scaling can also be utilized to reduce power consumption.
Reductive Chemistry of the Novel Hypoxia-Selective Cytotoxin 5-[N,N-Bis(2-chloroethyl)amino]-2,4-dinitrobenzamide (1995)

5-[N,N-Bis(2-chloroethyl)amino]-2,4-dinitrobenzamide (1; SN 23862) is a novel bioreductive drug whose selective toxicity for hypoxic cells appears due to oxygen-inhibited enzymatic reduction of one of the nitro groups to the corresponding amine or hydroxylamine. Radiolytic reduction of 1 using up to four reducing equivalents in 1 N sodium formate was shown to proceed via electron addition to the 4-nitro group, thereby identifying this substituent as the most electron-affinic site in the molecule. The initially-formed 4-hydroxylamine and its N-hydroxytetrahydroquinoxaline half-mustard cyclization product (formed by intramolecular reaction with one arm of the adjacent mustard group) are reduced to the corresponding 4-amines upon further addition of electrons, although reduction of the 2-nitro group leading to 2,4-diamino products begins after addition of only six electron equivalents. Radiolytic reduction of the structurally similar 5-(aziridin-1-yl)-2,4-dinitrobenzamide (2; CB 1954) with six electron equivalents also occurs at the 4-nitro group to give the 4-hydroxylamine and 4-amine. The product mixture from reduction of 2 is less complex, largely because the corresponding 4-hydroxylamine and 4-amine are stable. The major reduction products of 1 were chemically synthesized by unequivocal routes to provide authentic samples for identification of the products of radiolytic reduction and to allow determination of their cytotoxicities. The 2- and 4-amino derivatives of 1 are significantly more cytotoxic than the parent drug, although the toxicity of the 4-amine is moderated by its facile conversion to the corresponding less toxic tetrahydroquinoxaline half-mustard. Although the 2- and 4-hydroxylamino derivatives were prepared by chemical reduction of 1, their toxicity could not be evaluated because of their instability. The 4-hydroxylamine reacts intramolecularly with the 5-mustard group somewhat more rapidly than does the 4-amine, while the 2-hydroxylamine is converted into a 2,2'-azoxy dimer following aerial oxidation to the 2-nitroso derivative. The fully reduced 2,4-diamino derivative of 1 is 10-fold more cytotoxic again than the 2-amine and, surprisingly, does not undergo spontaneous intramolecular alkylation. This elucidation of the reduction chemistry of 1 will facilitate further investigations of the toxic products generated from this compound both by hypoxic tumor cells and by ADEPT enzymes.
Occipital plagiocephaly: an epidemic of craniosynostosis? (1997)

“A bizarre epidemic … 400% increase since 1992.” “Unkind cut: some physicians do unnecessary surgery on heads of infants.”1 These terms were used last year by the Wall Street Journal , in company with the British media, to report that the incidence of posterior skull asymmetry, or occipital plagiocephaly, and its surgical management, had increased to epidemic proportions. Such headlines have resulted in anxiety among parents, general practitioners, and paediatricians, and it is therefore important to be clear about the causes of the asymmetry.

One cause of plagiocephaly is craniosynostosis, which is premature fusion of the cranial sutures—the adaptive fibrous joints between the bones of the skull. The resulting abnormal skull shape is usually an isolated anomaly but it may be associated with a craniofacial syndrome such as that of Crouzon or Apert. The skull shape is predictable from the suture or sutures involved. Premature fusion of the lambdoid sutures, …
Volume changes in the binding of lanthanides to peptide analogs of loop II of calmodulin (1989)

The solution expansion accompanying coordination of lanthanide ions to synthetic peptide analogues of a metal-binding loop in calmodulin was determined by a density method. This study was designed to further test the hypothesis that the nonlinear expansions observed upon sequential addition of Ca2+ to intracellular calcium-binding proteins reflect principally upon the coordination event at specific binding sequences. Three peptides of 13 residues each were synthesized as analogues of binding loop II in mammalian calmodulin: Peptide I was the native analogue; peptide II contained an aspartyl in place of an asparaginyl residue at position 5 from the N-terminus; for peptide III, the aspartyl residue in position 3 of the native analogue was interchanged with the asparaginyl residue in position 5. Thus, the number of charged-oxygen donor atoms for coordination was the same in I and in III, but the latter peptide could permit two pairs of acidic groups to converge toward the metal ion as in some loops of these proteins. The observed expansions with different lanthanide ions to the same peptide varied appreciably, suggesting dissimilar structures [Gariépy et al. (1983) Biochemistry 22, 1765-1772]; coordination to the simpler tetracarboxylate sequestrants, on the other hand, generated an expansion profile approximately as expected from the properties of the lanthanide series. The largest expansions were generated with peptide II (having the additional acidic group) for all lanthanides tested.(ABSTRACT TRUNCATED AT 250 WORDS)
Eosinophilic Granulocytes and Damage-associated Molecular Pattern Molecules (DAMPs) (2006)

The development of a tumor over many years typically leads to reciprocal alternations in the host and the tumor, enabling tumor growth paradoxically in the setting of substantial necrosis and inflammation. When evaluating a tumor, it is important to assess 3 elements: (1) the quantity and quality of tumor-associated leukocytes, (2) their state of activation, and (3) tumor microenvironment. Peripheral blood eosinophilia and tumor-associated tissue eosinophilia are frequently associated with some tumor types and also found after immunotherapy with IL-2, IL-4, granulocyte-macrophage colony-stimulating factor, and antibody to CTLA-4. Within several tumor types including gastrointestinal tumors, tumor-associated tissue eosinophilia is associated with a significantly better prognosis. The converse is true in other tumor types such as differentiated oral squamous cell carcinoma. On the basis of the emergent data, tumor-associated eosinophils have at least 2 dominant nonoverlapping activities: (1) destructive effector functions potentially limiting tumor growth as well as causing recruitment and activation of other leukocytes, (2) immunoregulative and remodeling activities which suppress immune response and promote tumor proliferation. The mechanism by which eosinophils in particular are recruited into tumor tissue is largely unknown. Candidates for causing eosinophil chemotaxis into tumor tissue are the released damage-associated molecular pattern molecules (DAMPs) including the nuclear protein high mobility group box 1. High mobility group box 1 is released upon necrotic cell death and secreted by many cells, particularly during periods of nutrient, hypoxic, or oxidant stress. This overview on eosinophil biology in the context of cancer and necrosis, introduces intriguing and novel strategies targeting eosinophils to enable more effective biologic therapy for cancer patients.
Characteristics of a quasi-sh (shear horizontal) acoustic wave in Z-X lithium niobate plates (1994)

A SH (Shear Horizontal) type acoustic wave is one in which the particle displacement lies in the propagation surface, and is at right angles to the direction of wave propagation. SH waves have recently attracted much attention for use in measuring properties of liquids and in liquid-phase-based chemical and biological sensors. This paper shows, for the first time, that a quasi-SH acoustic wave can exist in thin plates of Z-X lithium niobate. The wave is actually a Lamb wave (The A <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> Lamb wave mode) in which all three components of particle displacement are present. The shear horizontal component, however, becomes dominant if the ratio h/λ (h=plate thickness, λ=acoustic wavelength) becomes less than about 0.5. Attractive properties of this quasi-SH wave include: (a) phase velocity nearly constant for all values of h/λ, (b) ability to propagate in contact with a liquid medium, and (c) electromechanical coupling coefficient, K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> that reaches a maximum value as high as 0.15. These properties make the wave attractive for use in a variety of sensor and signal processing applications. Experimental measurements of phase velocity and coupling coefficient of the mode are found to be in fair agreement with theoretical calculations. An example of sensor applications is illustrated by using the wave to measure conductivity of liquids (aqueous KCl solution). The frequency of a 12 MHz quasi-SH mode oscillator fabricated on a 0.48 λ thick plate is found to vary by more than 80 kHz for variation in KCl concentration from 0 to 0.15%
Abnormal dark adaptation and rhodopsin kinetics in Sorsby's fundus dystrophy. (1992)

Scotopic visual thresholds and time courses for dark adaptation were determined in eight patients with Sorsby's fundus dystrophy. Rhodopsin regeneration also was recorded in two. All patients had poor night vision and a visible yellow deposit at the level of Bruch's membrane that was confluent in the posterior pole. In retinal regions with the yellow deposit, scotopic thresholds were elevated, the rod-cone break was delayed or indistinct, the time courses for the rod portion of the dark adaptation curve was prolonged, and rhodopsin regeneration was slow in the one patient in whom measurements were made. In regions of ophthalmoscopically normal retina, dark adaptation was affected minimally, and in one patient, rhodopsin was regenerated at a normal rate. It was hypothesized that the abnormal dark adaptation and rhodopsin kinetics might be caused by reduced metabolic exchange across a thickened Bruch's membrane.
Adaptive channel precoding for slowly fading channels (2002)

The bit error rate (BER) performance of a mobile or personal radio digital communications system at a high bit rate can be increased significantly by intersymbol interference (ISI) due to multipath propagation. In this paper, a novel adaptive channel precoder is proposed to improve the system performance with-out increasing the complexity of the portable unit. In the forward link, both the amplitude and phase of the signal carrier are predistorted at the transmitter of the base station, so that the signal received at the portable unit is ISI free (in the ideal case). The precoding is based on channel information estimated (from the reverse link) at the receiver of the base station. Computer simulation results demonstrate that, over a two-path Rayleigh fading channel, differential QPSK with the precoder has significantly lower BER values than those with a conventional decision feedback equalizer (DFE), because the precoder is not subject to error propagation.
Progress in the Treatment of Advanced Prostate Cancer (2014)

The androgen receptor (AR) is the most significant target for patients with metastatic castration-resistant prostate cancer (mCRPC). There is now irrefutable evidence that the AR axis is functional in most patients throughout the history of prostate cancer, is crucial from diagnosis to death, even in patients who have received hormonal manipulation, and represents a relevant therapeutic target in all phases of the disease. The potential mechanisms of tumor escape after castration are multifold, with each mechanism today representing a therapeutic opportunity. Phase III trials have been able to demonstrate improved overall survival (OS), improved quality of life, decreased skeletal-related events, and other important clinical benefits in young and elderly patients. After the initial positive results with docetaxel chemotherapy in improving OS, further research has resulted in five new treatments in the past few years. Immunotherapy with sipuleucel-T, cabazitaxel chemotherapy, the androgen biosynthesis inhibitor abiraterone acetate, the antiandrogen enzalutamide, and the radioisotope radium-223 have all been shown to improve OS in large-scale, well-conducted clinical trials. Proper understanding of mechanisms of resistance and of cross-resistance among these agents, sequencing, and combinations is now a priority.
Carbohydrate Metabolism in Bacteria (1973)

Human coronavirus (HCoV) infection causes respiratory diseases with mild to severe outcomes. In the last 15 years, we have witnessed the emergence of two zoonotic, highly pathogenic HCoVs: severe acute respiratory syndrome coronavirus (SARS-CoV) and ...Read More
Natural Disasters and Other Emergencies beyond Control: Assistance by the IMF (1990)

s assistance is directed toward
The chrysanthemumcarboxylic acids. V.—hydration of the chrysanthemic acids (1952)

Abstract In boiling dilute sulphuric acid hydration of (±)‐ trans ‐chrysanthemic acid occurs to give the crystalline (±)‐ trans ‐δ‐hydroxydihydrochrysanthemic acid. In like manner (+)‐and (‐)‐ trans ‐chrysanthemic acids yield the crystalline (‐)‐ and (+)‐ trans ‐δ‐hydroxy‐dihydrochrysanthemic acids respectively. No racemization occurs as the recovered ( + )‐and ( ‐ )‐ trans ‐chrysanthemic acids have unchanged specific rotation. The lactonization of (±)‐ cis ‐chrysanthemic acid to (±)‐ cis ‐dihydrochrysanthemo‐δ‐lactone in boiling dilute sulphuric acid is shown to be reversible and to constitute an example of lacto‐enoic tautomerism. ( + )‐ and ( ‐ )‐ cis ‐Chrysanthemic acids are similarly lactonized to the crystalline (+)‐ and (‐)‐ cis ‐dihydrochrysanthemo‐δ‐lactones. The latter lactone is not identical with (‐)‐pyrocin, whose structure is confirmed as (‐)‐β‐ iso butenyl iso ‐hexano‐γ‐lactone.
Amplified phase-conjugate beam reflection by four-wave mixing with photorefractive Bi_12SiO_20 crystals (1984)

Phase-conjugate beam reflectivity in photorefractive Bi12SiO20 (BSO) crystals is analyzed as a function of the following parameters involved in the four-wave mixing interaction: grating spatial frequency Λ−1, applied field E0, and incident beam ratio β. We report an amplified reflectivity (R = 2.7) for asymmetric pump-beam intensities and optimized fringe-displacement speed (moving-grating recording mode, E0 = 10 kV cm−1; Λ−1 ≃ 45 mm−1; β > 104). The conjugate-beam reflectivity is shown to depend closely on the same parameters as the exponential gain coefficient Γ of the two-wave mixing configuration. Still higher reflectivities (R′ = 35) are demonstrated by using a combination of two BSO crystals whose roles are, respectively, to generate and then to amplify the conjugate beam.
In vivo growth-inhibition of Sarcoma 180 by piplartine and piperine, two alkaloid amides from Piper (2006)

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg(-1) day(-1) intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3% for piplartine and 55.1 and 56.8% for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.