gebhart/patrepeval huggingface dataset:
Spatio-temporal analysis of auditory cortex activation as detected with silent event related fMRI (2005)

Functional magnetic resonance imaging (fMRI) allows neuroscientists to assess brain function by evaluating haemodynamic activity (blood flow) when a stimulus is present or absent. In clinical practice, the hearing levels of individuals are determined using an audiometer that allows presentation of a pure-tone of specific intensity and frequency. Functional images of the auditory nervous system have been obtained using stimuli such as pure-tone, speech, noise, etc. However, the observed activation evoked by the stimulus is confounded with the neuronal response evoked by scanner noise generated during imaging. Hence, researchers have been developing fMRI techniques to overcome the inadvertent effect of scanner noise on fMRI studies of the auditory cortex. Silent event related fMRI is a recently reported fMRI technique diminishing the confounding effects of background scanner noise. A drawback of sfMRI is that it requires long acquisition times (30-40 min) to achieve statistically significant activation. An additional complication associated with all fMRI data is that measurements obtained at consecutive times tend to exhibit substantial temporal correlation. Such correlation structure complicates the identification of brain locations (voxels) demonstrating statistically significant activation. We propose an approach for detecting activation with high statistical power and low false-positive rate. To accomplish these goals of high power and low type I error rate in sfMRI with shorter acquisition times, we describe a statistical model that accounts for the spatial and temporal correlation structure of the haemodynamic response. Temporal dependence within each voxel's measurements is modelled, and a regional measurement-error-free kriging predictor is used to combine information from neighbouring voxels when assessing voxel activation. Instead of simply applying a post hoc smoothing to thevoxelwise test statistics (e.g. t statistics), we attempt to make optimal use of information in the locality of each voxel when estimating the voxel's mean, variance, and temporal dependence parameters. The primary advantage to this spatial modelling approach is that the degree to which voxel parameters are smoothed is driven by the data. Thus, we are not subjectively smoothing noisy data, but objectively estimating the noise-free version of the spatial processes associated with the response. The resulting voxel activation maps exhibit substantially more spatial continuity than other currently used approaches, while exhibiting desirable inferential properties including a lower false-positive rate and high power for detection of activated regions. Minimal computational resources are necessary to carry out the approach, which yielded voxel activation maps for our experiment in only minutes.
Terahertz epsilon-near-zero graded-index lens (2013)

An epsilon-near-zero graded-index converging lens with planar faces is proposed and analyzed. Each perfectly-electric conducting (PEC) waveguide comprising the lens operates slightly above its cut-off frequency and has the same length but different cross-sectional dimensions. This allows controlling individually the propagation constant and the normalized characteristic impedance of each waveguide for the desired phase front at the lens output while Fresnel reflection losses are minimized. A complete theoretical analysis based on the waveguide theory and Fermat's principle is provided. This is complemented with numerical simulation results of two-dimensional and three-dimensional lenses, made of PEC and aluminum, respectively, and working in the terahertz regime, which show good agreement with the analytical work.
Molecular Determinants of the Interaction between Clostridium perfringens Enterotoxin Fragments and Claudin-3 (2009)

Clostridium perfringens enterotoxin (CPE) binds to the extracellular loop 2 of a subset of claudins, e.g. claudin-3. Here, the molecular mechanism of the CPE-claudin interaction was analyzed. Using peptide arrays, recombinant CPE-(116-319) bound to loop 2 peptides of mouse claudin-3, -6, -7, -9, and -14 but not of 1, 2, 4, 5, 8, 10-13, 15, 16, 18-20, and 22. Substitution peptide mapping identified the central motif (148)NPL(150)VP, supposed to represent a turn region in the loop 2, as essential for the interaction between CPE and murine claudin-3 peptides. CPE-binding assays with claudin-3 mutant-transfected HEK293 cells or lysates thereof demonstrated the involvement of Asn(148) and Leu(150) of full-length claudin-3 in the binding. CPE-(116-319) and CPE-(194-319) bound to HEK293 cells expressing claudin-3, whereas CPE-(116-319) bound to claudin-5-expressing HEK293 cells, also. This binding was inhibited by substitutions T151A and Q156E in claudin-5. In contrast, removal of the aromatic side chains in the loop 2 of claudin-3 and -5, involved in trans-interaction between claudins, increased the amount of CPE-(116-319) bound. These findings and molecular modeling indicate different molecular mechanisms of claudin-claudin trans-interaction and claudin-CPE interaction. Confocal microscopy showed that CPE-(116-319) and CPE-(194-319) bind to claudin-3 at the plasma membrane, outside cell-cell contacts. Together, these findings demonstrate that CPE binds to the hydrophobic turn and flanking polar residues in the loop 2 of claudin-3 outside tight junctions. The data can be used for the specific design of CPE-based modulators of tight junctions, to improve drug delivery, and as chemotherapeutics for tumors overexpressing claudins.
An investigation of lateral current injection laser internal operation mechanisms (1995)

Lateral current injection (LCI) lasers have the potential to overcome many of the limitations inherent to conventional vertical injection structures, but until now there has been very little theoretical analysis and optimization of LCI laser designs, 2-D self-consistent simulations of these devices have been carried out to analyze the electrical and optical characteristics of several recently fabricated devices. These simulations are in good agreement with available experimental results and offer explanations for the observed roll-off in differential slope efficiency. In addition, we have explored some key design issues unique to LCI lasers such as the cause and consequences of the non-uniform gain profile, ways to minimize this non-uniformity, and the effects limiting the device speed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Chemiluminescence of Luminol and Its Synthesis from Easily Available Chemicals (2008)

Chemiluminescence, a low-temperarure light emission due to a chemical reaction, is demonstrated on the reaction of luminol (5-amino-2,3-dihydrophthalazine-1,4-dione), hydrogen peroxide, potassium hexacyanoferrate(III) and alkaline hydroxide. The synthesis of luminol from common chemicals and its impressive chemiluminescence are described.
Tree and spline based association analysis of gene–gene interaction models for ischemic stroke (2004)

In the biology of complex disorders, such as atherothrombosis, interactions among genetic factors may play an important role, and theoretical considerations suggest that gene-gene interactions are quite common in such diseases. We used a nested case-control sample from the Physicians' Health Study, a randomized trial assessing the effects of aspirin and beta-carotene on cardiovascular disease and cancer among 22071 US male physicians, to examine these relationships for ischemic stroke. Data were available on 92 polymorphisms from 56 candidate genes related to inflammation, thrombosis and lipid metabolism, assessed in 319 incident cases of ischemic stroke and 2090 disease-free controls. We used classification and regression trees (CART) and multivariate adaptive regression spline (MARS) models to explore the presence of genetic interactions in these data. These models offer advantages over typical logistic regression methods in that they may uncover interactions among genes that do not exhibit strong marginal effects. Final models were selected using either the Bayes Information Criterion or cross-validation. Model fit was assessed using 10-fold cross-validation of the entire selection process. Both the CART and two-way MARS-logit models identified an interaction between two polymorphisms linked to inflammation, the P-selectin (val640leu) and interleukin-4 (C(582) T) genes. Internal validation of these models, however, suggested that effects of these polymorphisms are additive. Although further external validation of these models is necessary, these methods may be valuable in exploring and identifying potential gene-gene as well as gene-environment interactions in association studies.
Cyclopentadienyls of titanium, zirconium, and hafnium (1970)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCyclopentadienyls of titanium, zirconium, and hafniumGeorge W. Watt and Frank O. Drummond Jr.Cite this: J. Am. Chem. Soc. 1970, 92, 4, 826–828Publication Date (Print):February 1, 1970Publication History Published online1 May 2002Published inissue 1 February 1970https://pubs.acs.org/doi/10.1021/ja00707a015https://doi.org/10.1021/ja00707a015research-articleACS PublicationsRequest reuse permissionsArticle Views256Altmetric-Citations48LEARN 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
Regulation of CR3 (CD11b/CD18)-dependent natural killer (NK) cell cytotoxicity by tumour target cell MHC class I molecules (1999)

Phagocyte and NK cell CR3 functions as both an adhesion molecule and an iC3b receptor mediating cytotoxic responses to microorganisms. Cytotoxic activation of iC3b receptor function requires ligation of both a CD11b I-domain site for iC3b and a lectin site located in the C-terminus of CD11b. Because tumours lack the CR3-binding polysaccharides of bacteria and fungi, iC3b-opsonized tumours do not stimulate CR3-dependent cytotoxicity. Previous studies showed that NK cells could be induced to kill iC3b-opsonized tumours with small soluble beta-glucans that bound with high affinity to CR3, bypassing the absence of similar polysaccharides on tumour membranes. Because CR3 signalling requires several tyrosine phosphorylation events, it appeared possible that CR3-dependent killing of autologous tumour cells might be suppressed by NK cell inhibitory receptors for MHC class I (KIR and CD94/NKG2) whose action involves recruitment of SHP-1 and SHP-2 tyrosine phosphatases. In the current study, Epstein-Barr virus (EBV)-transformed B cells were used as targets following opsonization with iC3b. Soluble beta-glucan primed CR3 for killing of iC3b-coated B cells, but autologous class I-bearing targets were 84% more resistant than class I-deficient Daudi cells. Blockade of target cell class I with a MoAb specific for a domain recognized by both KIR and CD94/NKG2 resulted in comparable killing of class I+ B cells. By contrast, another MoAb to class II had no effect on cytotoxicity. These data suggest that NK cell recognition of class I suppresses CR3/tyrosine kinase-dependent cytotoxicity in the same way as it suppresses cytotoxicity mediated by other tyrosine kinase-linked receptors such as FcgammaRIIIA (CD16).
Why Bis(fluorosulfonyl)imide Is a “Magic Anion” for Electrochemistry (2014)

Ionic liquids consisting of bis(fluorosulfonyl)imide (FSI–) anion show promise as electrolytes for Li-ion-based electric storage devices, as they exhibit relatively low viscosity, high chemical stability, and form robust solid–electrolyte interphase (SEI) protecting liquid electrolyte from further breakdown on the electrode. These ionic liquids have been reported to inhibit dendrite formation on lithium metal and lithiated graphite electrodes, which also relates to the unusual SEI properties. In this study, we examine the chemistry aspects that may account for this behavior. Radiolysis was used to induce redox reactions of FSI– anions in model systems, and matrix isolation electron paramagnetic resonance was used to identify radical (ion) intermediates generated in these reactions. Our results suggest that qualitative differences between such ionic liquid electrolytes versus common carbonate electrolytes reflect ease of mineralization of the reduced anion without the concurrent generation of organic radicals and/or elimination of gaseous products in side reactions of the corresponding radical intermediates.
Watermarking 2D vector maps in the mesh-spectral domain (2003)

The paper proposes a digital watermarking algorithm for 2D vector digital maps. The watermark is a robust, informed-detection watermark to be used to prevent such abuses as an intellectual property rights violation. The algorithm proposed in the paper embeds watermarks in the frequency-domain representation of a 2D vector digital map. Our method treats vertices in the map as a point set, and imposes connectivity among the points by using Delaunay triangulation. The method then computes the mesh-spectral coefficients (Karni, 2000) from the mesh created. Modifications of the coefficients according to the message bits, and inverse transforming the coefficients back into the coordinate domain produces the watermarked map. Our evaluation experiments showed that the watermark produced by the method is resistant against additive random noise, similarity transformation, vertex insertion and removal. It is also resistant, to some extent, against cropping. Compared to our previous algorithm (Ohbuchi, 2002), the algorithm described in this paper showed significantly improved attack resiliency.
5′-Methylthioadenosine Nucleosidase and 5-Methylthioribose Kinase Activities and Ethylene Production during Tomato Fruit Development and Ripening (1985)

5'-Methylthioadenosine (MTA) nucleosidase and 5-methylthioribose (MTR) kinase activities were measured in crude extracts of tomato fruits (Lycopersicon esculentum Mill cv Rutgers) during fruit development and ripening. The highest activity of MTA nucleosidase (1.2 nanomoles per milligram protein per minute) was observed in small green fruits. The activity decreased during ripening; at the overripe stage only 6.5% of the peak activity remained. MTR kinase activity was low at the small green stage and increased thereafter until it reached peak activity at the breaker stage (0.7 nanomoles per milligram protein per minute) followed by a sharp decline at the later stages of fruit ripening. 1-Amino-cyclopropane-1-carboxylic acid (ACC) levels peaked at the red stage, while ethylene reached its highest level at the light-red stage. Several analogs of MTA and MTR were tested as both enzyme and ethylene inhibitors. Of the MTA analogs examined for their ability to inhibit MTA nucleosidase, 5'-chloroformycin reduced enzyme activity 89%, whereas 5'-chloroadenosine, 5'-isobutylthioadenosine, 5'-isopropylthioadenosine, and 5'-ethylthioadenosine inhibited the reaction with MTA by about 40%. 5'-Chloroformycin and 5'-chloroadenosine inhibited ethylene production over a period of 24 hours by about 64 and 42%, respectively. Other analogs of MTA were not effective inhibitors of ethylene production, whereas aminoethoxyvinylglycine showed a 34% inhibition over the same period of time. Of the MTR analogs tested, 5-isobutylthioribose was the most effective inhibitor of both MTR-kinase (41%) and ethylene production (35%).
Fully differential basic building blocks based on fully differential difference amplifiers with unity-gain difference feedback (1995)

A set of truly fully differential (FD) basic building blocks is presented. They are based on differential difference amplifiers with differential output (FDDA, fully differential difference amplifier) in unity gain difference feedback configuration. Simulation results at the transistor level demonstrate their suitability for FD signal processing.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Preparation of Aluminum Nitride Epitaxial Films by Electron Cyclotron Resonance Dual-Ion-Beam Sputtering (1994)

Aluminum nitride (AlN) thin films have been deposited on (11̄·2) sapphire by an electron cyclotron resonance (ECR) dual-ion-beam sputtering method. We have thoroughly investigated the dependence of the crystallinity and surface smoothness of the AlN thin film on the assisted conditions and sputtering conditions. The AlN thin film deposited under assisted conditions with the nitrogen ion beam energy and current density of 100 eV and 0.32 mA/cm 2 , respectively, and sputtering conditions with the arrival aluminum flux rate to the substrate surface (Al flux rate) and argon (Ar) ion beam energy of 42 Å/min and 800 eV, respectively, is a single-crystal film with a very smooth surface. In order to prepare the epitaxial film, the Ar ion beam energy must be increased according to increases in the Al flux rate, and decreased according to decreases in the Al flux rate.
Observation of counterclockwise, clockwise and butterfly bistabilty in 1550 nm VCSOAs (2007)

In this paper, we report counter-clockwise, clockwise, and, for the first time to our knowledge, butterfly bistability in 1550 nm Vertical Cavity Semiconductor Optical Amplifiers (VCSOA). Bistable operation is experimentally observed for bias currents ranging from 66-122% of threshold with switching powers as low as 2 microW. These switching powers are two orders of magnitude lower than any previous results in 1550 nm VCSOAs. These switching powers are consistent with previous reports on optical bistability in 850 nm VCSOAs and provide an important step towards the realization of small footprint, low power optical logic/switching elements in the 1550 nm wavelength band.
A Practitioner’s Guide to Establishing a Prudent Transition Process (2009)

The hallmark of a successful transition is often defined by the ability of asset owners to manage all of their risks - operational, fiduciary, performance, as well as execution. This challenge is exacerbated by the fact that, while transition management firms offer a variety of execution strategies, the lines between their business models are blurring. As fiduciaries, asset owners are not, of course, expected to have a crystal ball. Rather, the metric by which their decisions are evaluated should be the prudence of their process. It is therefore essential that asset owners have a thorough understanding of all facets of their transition portfolios. Such knowledge is a prerequisite to establishing optimal transition strategies and providing comfort that appropriate safeguards are in place to maximize client confidentiality and minimize conflicts of interest. In practice, this calls for a blend of strategic and tactical considerations that balance theoretical “best practices” against practical necessity. This article provides a summary of specific issues asset owners should review when trying to construct prudent transition strategies, and critical questions asset owners should ask prior to hiring their transition managers. It also identifies conflicts of interest, revenue generation, fiduciary responsibility, pre-hedging, cost estimation, pre-transition planning, trade implementation, and post-transition evaluation as essential issues asset owners should consider when faced with the need to transition assets within their funds. It further identifies key due-diligence action items for asset owners, and offers a roadmap to asset owners regarding transition management best practices and uniform protocols.
Single missense mutation in the tyrosine kinasecatalytic domain of the RET protooncogene is associated with multiple endocrineneoplasia type 2B. (1994)

Multiple endocrine neoplasia type 2B (MEN 2B) is a human cancer syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytomas, mucosal neuromas, ganglioneuromas of the intestinal tract, and skeletal and ophthalmic abnormalities. It appears both as an inherited disorder and as de novo disease. Sequence analysis of germ-line DNA from MEN 2B patients revealed the existence of the same point mutation in the RET protooncogene in 34 unrelated individuals. This sequence difference was not observed in 93 unaffected individuals, including the normal parents of 14 de novo MEN 2B patients. The mutation (ATG-->ACG) results in the replacement of methionine with threonine within the catalytic core region of the tyrosine kinase domain. We propose that this amino acid replacement effects substrate interactions and results in dominant oncogenic activity by the RET protein. Missense mutations in the extracellular ligand-binding domain of the RET protooncogene previously have been associated with two other disorders [MEN 2A and familial MTC (FMTC)] in which MTC is observed. MEN 2B represents the third form of heritable MTC known to be an allele of RET. Alterations in two different functional domains of the putative receptor protein tyrosine kinase are implicated in development of MTC.
Characterization of the local mechanical stress induced during the Ti and Co/Ti salicidation in sub-0.25 μm technologies (1999)

In this article, micro-Raman spectroscopy measurements of the local mechanical stress in the silicon substrate induced by the Ti and Co/Ti salicidation were combined with simulations by finite element modeling down to 0.1 μm technologies. It is shown that the scaling possibilities of TiSi2 and of CoSi2 will both be hampered by the stress induced during the salicidation and will result in the generation of 60° dislocations in the silicon substrate. These experiments prove that, because of the difference in material properties between TiSi2 and CoSi2, a higher stress is generated in the silicon substrate during the Ti salicidation than during the low stress Co/Ti-salicidation process. Therefore, the mechanical characteristics related to the silicide formation become a critical parameter in the optimization of the silicide process.
Robust helical spring microbalance (1961)

An account is given of the construction of a simple null-reading microbalance which has been used for low-temperature magnetic susceptibility measurements and may have wider applications.
A scalable dual mode arithmetic unit for public key cryptosystems (2005)

Elliptic curve cryptosystems (ECC) have become popular in recent years due to their smaller key sizes than traditional public key schemes such as RSA. However the gap between the sizes of these systems is increasing as security requirements become more demanding due to cryptanalytic advances. At current security levels of 80 bits, the corresponding key sizes for ECC and RSA are J60 and 1,024 bits respectively. Although the ECC key size is attractive for embedded applications, the popularity of RSA means that it will remain in legacy applications for the foreseeable future. This paper proposes a dual mode arithmetic unit capable of supporting the underlying field operations performed by both the ECC and RSA public key schemes. A hardware optimized version of the Montgomery algorithm is employed to perform modular multiplication efficiently. The disparity in key sizes is addressed by combining the dual processors to operate in parallel for ECC or in a pipelined series for RSA.