gebhart/patrepeval huggingface dataset:
The ALK-2 and ALK-4 activin receptors transduce distinct mesoderm-inducing signals during early <i>Xenopus</i> development but do not co-operate to establish thresholds (1997)

The TGFbeta family member activin induces different mesodermal cell types in a dose-dependent fashion in the Xenopus animal cap assay. High concentrations of activin induce dorsal and anterior cell types such as notochord and muscle, while low concentrations induce ventral and posterior tissues such as mesenchyme and mesothelium. In this paper we investigate whether this threshold phenomenon involves the differential effects of the two type I activin receptors ALK-2 and ALK-4. Injection of RNA encoding constitutively active forms of the receptors (here designated ALK-2* and ALK-4*) reveals that ALK-4* strongly induces the more posterior mesodermal marker Xbra and the dorsoanterior marker goosecoid in animal cap explants. Maximal levels of Xbra expression are attained using lower concentrations of RNA than are required for the strongest activation of goosecoid, and at the highest doses of ALK-4*, levels of Xbra transcription decrease, as is seen with high concentrations of activin. By contrast, the ALK-2* receptor activates Xbra but fails to induce goosecoid to significant levels. Analysis at later stages reveals that ALK-4* signalling induces the formation of a variety of mesodermal derivatives, including dorsal cell types, in a dose-dependent fashion, and that high levels also induce endoderm. By contrast, the ALK-2* receptor induces only ventral mesodermal markers. Consistent with these observations, ALK-4* is capable of inducing a secondary axis when injected into the ventral side of 32-cell stage embryos whilst ALK-2* cannot. Co-injection of RNAs encoding constitutively active forms of both receptors reveals that ventralising signals from ALK-2* antagonise the dorsal mesoderm-inducing signal derived from ALK-4*, suggesting that the two receptors use distinct and interfering signalling pathways. Together, these results show that although ALK-2* and ALK-4* transduce distinct signals, the threshold responses characteristic of activin cannot be due to interactions between these two pathways; rather, thresholds can be established by ALK-4* alone. Furthermore, the effects of ALK-2* signalling are at odds with it behaving as an activin receptor in the early Xenopus embryo.
X-ray image reconstruction from a diffraction pattern alone (2003)

A solution to the inversion problem of scattering would offer aberration-free diffraction-limited three-dimensional images without the resolution and depth-of-field limitations of lens-based tomographic systems. Powerful algorithms are increasingly being used to act as lenses to form such images. Current image reconstruction methods, however, require the knowledge of the shape of the object and the low spatial frequencies unavoidably lost in experiments. Diffractive imaging has thus previously been used to increase the resolution of images obtained by other means. Here we experimentally demonstrate an inversion method, which reconstructs the image of the object without the need for any such prior knowledge.
Efficient foreground-background segmentation using local features for object detection (2015)

In this work, a local feature based background modelling for background-foreground feature segmentation is presented. In local feature based computer vision applications, a local feature based model presents advantages with respect to classical pixel-based ones in terms of informativeness, robustness and segmentation performances. The method discussed in this paper is a block-wise background modelling where we propose to store the positions of only most frequent local feature configurations for each block. Incoming local features are classified as background or foreground depending on their position with respect to stored configurations. The resulting classification is refined applying a block-level analysis. Experiments on public dataset were conducted to compare the presented method to classical pixel-based background modelling.
Laser Peening without Coating as a Surface Enhancement Technology (2006)

Laser peening without coating (LPwC) is an innovative surface enhancement technology, which imparts compressive residual stress without any surface preparations. Materials were peened in aqueous environment with laser pulses of about 100 mJ from a Q-switched and frequency-doubled Nd:YAG laser. Surface roughness of the materials somewhat increased due to ablative interaction. Compressive residual stress nearly equal to the yield strength of the materials appeared at the surface after LPwC in spite of the possible heat effect by direct laser irradiation to the materials. The depth of the compression reaches 1 mm or more from the peened surface. High-cycle fatigue properties were evaluated through rotating-bending or push-pull type testing for an austenitic stainless steel (SUS316L), a titanium alloy (Ti-6Al-4V) and a cast aluminum alloy (AC4CH). LPwC significantly prolonged the fatigue lives despite the increase in surface roughness. Accelerating stress corrosion cracking (SCC) tests showed that LPwC completely eliminated SCC susceptibility of sensitized austenitic stainless steels, nickel-based alloys and their weld metals. LPwC has been utilized to prevent SCC in Japanese nuclear power reactors since 1999.
Recombinant Anti-Human HER2/ <i>neu</i> IgG3-(GM-CSF) Fusion Protein Retains Antigen Specificity and Cytokine Function and Demonstrates Antitumor Activity (2000)

Anti-HER2/neu therapy of human HER2/neu-expressing malignancies such as breast cancer has shown only partial success in clinical trials. To expand the clinical potential of this approach, we have genetically engineered an anti-HER2/neu IgG3 fusion protein containing GM-CSF. Anti-HER2/neu IgG3-(GM-CSF) expressed in myeloma cells was correctly assembled and secreted. It was able to target HER2/neu-expressing cells and to support growth of a GM-CSF-dependent murine myeloid cell line, FDC-P1. The Ab fusion protein activated J774.2 macrophage cells so that they exhibit an enhanced cytotoxic activity and was comparable to the parental Ab in its ability to effect Ab-dependent cellular cytotoxicity-mediated tumor cell lysis. Pharmacokinetic studies showed that anti-HER2/neu IgG3-(GM-CSF) is stable in the blood. Interestingly, the half-life of anti-HER2/neu IgG3-(GM-CSF) depended on the injected dose with longer in vivo persistence observed at higher doses. Biodistribution studies showed that anti-HER2/neu IgG3-(GM-CSF) is mainly localized in the spleen. In addition, anti-HER2/neu IgG3-(GM-CSF) was able to target the HER2/neu-expressing murine tumor CT26-HER2/neu and enhance the immune response against the targeted Ag HER2/neu. Anti-HER2/neu IgG3-(GM-CSF) is able to enhance both Th1- and Th2-mediated immune responses and treatment with this Ab fusion protein resulted in significant retardation in the growth of s.c. CT26-HER2/neu tumors. Our results suggest that anti-HER2/neu IgG3-(GM-CSF) fusion protein is useful in the treatment of HER2/neu-expressing tumors.
Selective stimulation of epithelial cells in colonic crypts: relation to active chloride secretion (1995)

Stimulation of Cl secretion by prostaglandin E2 (PGE2) was measured as the short-circuit current (Isc) across isolated epithelium of the rabbit distal colon. Cellular morphology of columnar and goblet cells during secretion was monitored using light and electron microscopy. Stimulation by PGE2 altered epithelial cell morphology only by a reduction of vacuolar space in the apical pole of crypt columnar cells, consistent with release of vacuole contents. Imaging of isolated crypts using differential interference microscopy confirmed the release of material from columnar cells during the onset of secretion. Inhibition of Cl secretion with the loop diuretic bumetanide did not block vacuole release. The actin filament-disrupting agent, cytochalasin, reduced the PGE2-stimulated Isc by 40% and blocked emptying of the vacuolar space. These electrical and morphological results indicate that the process of active ion secretion is associated with release of the macromolecular contents from apical vacuoles through a mechanism involving the cytoskeleton. In addition, this relationship supports the concept that vacuolated columnar cells of the crypts of Lieberkühn are the cell type that secretes Cl in response to PGE2.
Empirical properties of asset returns: stylized facts and statistical issues (2001)

We present a set of stylized empirical facts emerging from the statistical analysis of price variations in various types of financial markets. We first discuss some general issues common to all statistical studies of financial time series. Various statistical properties of asset returns are then described: distributional properties, tail properties and extreme fluctuations, pathwise regularity, linear and nonlinear dependence of returns in time and across stocks. Our description emphasizes properties common to a wide variety of markets and instruments. We then show how these statistical properties invalidate many of the common statistical approaches used to study financial data sets and examine some of the statistical problems encountered in each case.
Identification of open-loop transfer functions in closed-loop baroreflex system using random breathing in humans (2003)

The existence of feedback loop in the baroreflex system makes it difficult to determine the open-loop transfer function characteristic of the central arc by which blood pressure (BP) modulates sympathetic nerve activity (SNA) and the peripheral arc by which SNA modulates BP. Random aortic pressure perturbation and electrical stimulation of aortic depressor nerve have been proposed to identify these open-loop characteristics under closed loop conditions in animals, but are limited of application in humans. We explored the random breathing technique to identify open-loop characteristics under closed-loop condition in 14 healthy subjects (10 m/4f 27/spl plusmn/2years, mean S.E.). Random interval breathing (RB) can perturb BP with white noise characteristics over the physiologically relevant frequency range of 0.01-0.3 Hz. We measured the muscle SNA of the peroneal nerve and the continuous BP. The peripheral arc transfer function (SNA/spl rarr/4BP) could be approximated by a second-order low-pass filter and the fitted parameters of dynamic gain, natural frequency, damping ratio, and lag time were 1.12/spl plusmn/0.35, 0.06/spl plusmn/0.01 Hz, 0.49/spl plusmn/0.14, and 1.05/spl plusmn/0.26 s, respectively. The central arc transfer function (BP/spl rarr/NA) could be approximated by a first-order high-pass filter and the fitted parameters of dynamic gain, corner frequency, and lag time were 1.75/spl plusmn/0.28, 0.1/spl plusmn/0.04 Hz, and 0.57/spl plusmn/0.18 s, respectively. In conclusion, the proposed random breathing technique is an useful tool of assessment in human autonomic nervous system for identification of open-loop transfer functions in the closed-loop baroreflex system.
140-μJ, narrow-linewidth, robustly single-transverse mode nanosecond infrared fiber laser platform with fine pulse tailoring capability (2009)

The work presented in this paper had two main objectives. The first objective was to develop a very stable nanosecond infrared pulsed fiber laser oscillator platform offering a straightforward and accurate control over the pulse characteristics in the time domain. The second objective was to deliver what we call "high quality photons", which means delivering pulses with high energy and excellent beam quality and narrow spectral linewidth, all at the same time and with very good stability. Oscillators with such attributes find applications in material processing fields, for example in memory repair, photovoltaic cell processing or micro-milling, to name just a few. In order to achieve the first objective, an embedded digital platform using high-speed electronics was developed. Using this platform and a computer, pulse shapes have been programmed straightforwardly in the non-volatile memory of the instrument, with an amplitude resolution of 10 bits and a time resolution of 2.5 ns. Optical pulses having tailored temporal profiles, with rise times around 1 ns and pulse energy stability levels better than ± 3% at 3σ, have been generated at high repetition rates (> 100 kHz) at a wavelength of 1064 nm. Achieving the second objective required amplifying the low power master oscillator signal (10-100 mW) to output power levels in the range of 1 to 50 W. A multi-clad, polarization maintaining, Yb-doped large mode area fiber was specially designed to allow for the amplification of high peak power optical pulses, while keeping control over the nonlinear effects and preserving an excellent beam quality. Optical pulses with tailored shapes and pulse energy levels in excess of 140 μJ have been produced for pulse durations in the range of 10 to 80 ns, with 86% of the power emitted in a 0.5-nm bandwidth. The linearly polarized beam M<sup>2</sup> parameter was smaller than 1.1, with both the astigmatism and the asymmetry below 15%. The pulse energy stability was better than ± 3% at 3σ. We conclude with a discussion about some of the applications of the developed platform.
Cryptic Angioma in the Trochlear Nerve. Excision of the Invaded Portion and Successful Repair with an Autologous Graft (1992)

Cryptic angiomas, which are intrinsic to cranial nerves, are uncommon. Such lesions involving the trochlear nerve have not been previously described. The authors have therefore found it interesting to report a case fortuitously discovered in a patient with trigeminal neuralgia who underwent a fifth nerve microvascular decompression through the supracerebellar space. The angioma was not responsible for the neuralgia, but because of its potential risk of bleeding, the lesion was treated by resection of the trochlear nerve in its invaded portion. Then, the nerve was successfully repaired with an autograft harvested from the distal part of the sural nerve.
On the mathematics of fluidization Part 1. Fundamental equations and wave propagation (1965)

When the upward flow of a fluid through a bed of particles of appropriate and almost uniform size is rapid enough so that the drag on each particle is as great as the particles buoyant weight, the particles do not remain close packed and the bed is said to be fluidized. Industrial uses of fluidized beds in the chemical and petroleum industries in particular are already extensive. Uses in the atomicenergy industry are being developed. In this paper a mathematical model which describes the phenomena on a continuum basis is deduced. With this model we find that the system is unstable to small internal disturbances. Alternatively, we find that surface waves can be propagated (with attenuation) in the composite fluid and these waves for fluidized beds with a high ratio of solids density to fluid density are stable. These results are in agreement with experiment. Hot beds, where strongly exothermic reactions may be taking place, centrifugal beds (beds fluidized within a rotating system), and electromagnetic beds (those in which the particulate phase is electrically conducting) are all shown to be unstable to small internal disturbances. The equations derived here may also be used as approximate equations for dispersed particle two-phase flow.
Performance of electro-optical plasmonic ring resonators at telecom wavelengths (2012)

In this work we report on the characteristics of an electro-optical dielectric-loaded surface plasmon polariton waveguide ring resonator. By doping the dielectric host matrix with an electro-optical material and designing an appropriate set of planar electrodes, we measured a 16% relative change of transmission upon application of a controlled electric field. We have analyzed the temporal response of the device and conclude that electrostriction of the host matrix is playing a dominating role in the transmission response.
Chemistry of the bis[.pi.-(3)-1,2-dicarbollyl] metalates of nickel and palladium (1970)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry of the bis[.pi.-(3)-1,2-dicarbollyl] metalates of nickel and palladiumLeslie F. Warren Jr. and M. Frederick HawthorneCite this: J. Am. Chem. Soc. 1970, 92, 5, 1157–1173Publication Date (Print):March 1, 1970Publication History Published online1 May 2002Published inissue 1 March 1970https://pubs.acs.org/doi/10.1021/ja00708a009https://doi.org/10.1021/ja00708a009research-articleACS PublicationsRequest reuse permissionsArticle Views355Altmetric-Citations111LEARN 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
Solid-State NMR Studies of the Preparation of Si−Al−C−N Ceramics from Aluminum-Modified Polysilazanes and Polysilylcarbodiimides (2004)

Multinuclear (13C, 29Si, 27Al, 1H) solid-state NMR spectroscopy and EPR and FT IR experiments are employed to investigate the thermolysis of aluminum-modified poly(hydridovinylsilazane), [Al(C2H4−SiHNH)3]n, from which Si−Al−C−N ceramics can be formed. In addition, a comparative study is provided for different aluminum-modified polysilazanes and polysilylcarbodiimides in the amorphous state at 1400 °C. The investigation primarily aims at the structural characterization of the amorphous intermediates, where such spectroscopic techniques have demonstrated their particular suitability. It is shown that the transformation of the polymeric precursor to the (amorphous) preceramic network is completed at around 500 °C. At this temperature AlN domains, as well as Si−C−N clusters of mixed composition, are formed. Above this temperature a continuous transformation to the ceramic material takes place. In addition, above 700 °C a considerable amount of free carbon-centered radicals is detectable. Eventually, three main components are found for the amorphous ceramic at 1050 °C which remain up to 1400 °C: (i) amorphous (graphite-like) carbon, (ii) AlN domains (with tetrahedral, pentagonal, and octahedral coordinated aluminum atoms), and (iii) a Si−C−N matrix (SiCxN4-x units with x = 0, 1, 2, 4). It is worthwhile to note that even at such high thermolysis temperatures a considerable amount of hydrogen can be detected as well. Comparative solid-state NMR experiments also have been performed on the amorphous ceramics fired at 1400 °C, derived from polysilazanes and polysilylcarbodiimides that differ in their basic structure as well as Si/N and Al/N ratios. For all samples the same basic components could be assigned. The actual composition of the amorphous ceramic, however, differs which can be related to the basic structure of the precursor polymer. In summary, the present spectroscopic study demonstrates that the introduction of aluminum atoms in the ternary Si−C−N matrix shows new aspects in the field of precursor ceramics.
Scalable optimal countermeasure selection using implicit enumeration on attack countermeasure trees (2012)

Constraints such as limited security investment cost precludes a security decision maker from implementing all possible countermeasures in a system. Existing analytical model-based security optimization strategies do not prevail for the following reasons: (i) none of these model-based methods offer a way to find optimal security solution in the absence of probability assignments to the model, (ii) methods scale badly as size of the system to model increases and (iii) some methods suffer as they use attack trees (AT) whose structure does not allow for the inclusion of countermeasures while others translate the non-state-space model (e.g., attack response tree) into a state-space model hence causing state-space explosion. In this paper, we use a novel AT paradigm called attack countermeasure tree (ACT) whose structure takes into account attacks as well as countermeasures (in the form of detection and mitigation events). We use greedy and branch and bound techniques to study several objective functions with goals such as minimizing the number of countermeasures, security investment cost in the ACT and maximizing the benefit from implementing a certain countermeasure set in the ACT under different constraints. We cast each optimization problem into an integer programming problem which also allows us to find optimal solution even in the absence of probability assignments to the model. Our method scales well for large ACTs and we compare its efficiency with other approaches.
Detection of shape deformities using Yamabe flow and Beltrami coefficients (2010)

We address the problem of detecting deformities on elastic surfaces. This is of great importance for shape analysis, with applications such as detecting abnormalities in biological shapes (e.g., brain structures). We propose an effective algorithm to detect abnormal deformations by generating quasi-conformal maps between the original and deformed surfaces. We firstly flatten the 3D surfaces conformally onto 2D rectangles using the discrete Yamabe flow and use them to compute a quasi-conformal map that matches internal features lying within the surfaces. The deformities on the elastic surface are formulated as non-conformal deformations, whereas normal deformations that preserve local geometry are formulated as conformal deformations. We then detect abnormalities by computing the Beltrami coefficient associated uniquely with the quasi-conformal map. The Beltrami coefficient is a complex-valued function defined on the surface. It describes the deviation of the deformation from conformality at each point. By considering the norm of the Beltrami coefficient, we can effectively segment the regions of abnormal changes, which are invariant under normal (non-rigid) deformations that preserve local geometry. Furthermore, by considering the argument of the Beltrami coefficient, we can capture abnormalities induced by local rotational changes. We tested the algorithm by detecting abnormalities on synthetic surfaces, 3D human face data and MRI-derived brain surfaces. Experimental results show that our algorithm can effectively detect abnormalities and capture local rotational alterations. Our method is also more effective than other existing methods, such as the isometric indicator, for locating abnormalities.