gebhart/patrepeval huggingface dataset:
Scanning secondary ion analytical microscopy with parallel detection (1992)

The secondary ion microscope described here allows to obtain the simultaneous registration of chemical and isotopic distribution maps of several elements composing the sample. The instrument has been specially designed to optimize both sensitivity and selectivity; bombardment with primary Cs+ ions to increase the ionization yields of negative secondary ions, efficient collection of secondary ions at the target surface, matching of the secondary ion beam etendue with the acceptance of the mass spectrometer working at high mass resolution, spectrometer with parallel detection capabilities. The probe diameter can be made as low as 30 nm and ion induced electron images registered at the same time as ion images. Presently, four ion micrographs are obtained simultaneously over a field of view up to 20 x 20 micro m2 containing up to 512 x 512 pixels. Examples are shown with an ion probe diameter of 0.1 microm.
System optics in both backprojection and forward projection for model-based iterative reconstruction (2012)

Advantages of iterative reconstruction (IR) algorithms over standard filtered backprojection (FBP) algorithms include improved resolution and better noise performance, and many IR algorithms have been described in the literature. More recently model-based IR algorithms (MBIR) have been developed, which incorporate accurate system models into IR, resulting in better image quality than IR algorithms without a system model. This work investigates the resolution improvement achieved when a system optics model (SOM) has been included in a standard OS-SART algorithm. Three OS-SART algorithms have been compared: (1) "Pencil beam" (IR-P) with no system optics; (2) system optics included in forward projection (IR-SOM-FP), and (3) system optics included in both forward and backprojection (IRSOM-FPBP). Simulated reconstructions of a 0.2 mm bead show that IR-SOM-FPBP produced a FWHM resolution of 0.41 mm, considerably better than FBPJ (0.87 mm), IR-P (0.63 mm), and IR-SOM-FP (0.59 mm).
Probing the shape of a hydrophobic pocket in the active site of <i>δ</i>‐opioid antagonists (2001)

The change of selectivity and the induction of antagonism by the insertion of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) in the second position of several opioid peptides have led to the interpretation of Tyr-Tic as a specific message domain for delta-opioid antagonists and to the discovery of dipeptides with substantial opioid activity. Selectivity and activity increase enormously when Tyr is substituted by 2',6'-dimethyl tyrosine (Dmt), hinting that the side chain of Dmt fits a hydrophobic cavity of the receptor very tightly and precisely. We have investigated the specificity of this fit by systematic changes of the substituents on the aromatic ring of ryr. Mono- and disubstitutions different from 2',6'- invariably lead to catastrophic decreases of activity. The only substitution compatible with retention of substantial antagonism is 2-methyl. An analysis of the conformational properties of all analogues reveals that substitutions do not affect the global shape of the molecule significantly. Accordingly, it is possible to use the shape of the different side chains to map the hydrophobic cavity of the receptor. The resulting complementary image is funnel shaped.
Effect of branching in remote substituents on light emission and stability of chemiluminescent acridinium esters (2014)

Acridinium dimethylphenyl esters are widely used as chemiluminescent labels in automated immunoassays for clinical diagnostics in Siemens Healthcare Diagnostics' ADVIA Centaur® systems.
Diabetic Retinopathy: Retina‐Specific Methods for Maintenance of Diabetic Rodents and Evaluation of Vascular Histopathology and Molecular Abnormalities (2015)

Diabetic retinopathy is a major cause of visual impairment, which continues to increase in prevalence as more and more people develop diabetes. Despite the importance of vision, the retina is one of the smallest tissues in the body, and specialized techniques have been developed to study retinopathy. This article summarizes several methods used to (i) induce diabetes in mice, (ii) maintain the diabetic animals throughout the months required for development of typical vascular histopathology, (iii) evaluate vascular histopathology of diabetic retinopathy, and (iv) quantitate abnormalities implicated in the development of the retinopathy.
Implementation of a Matrix Converter Space Vector Control in Programmable Logic (2003)

To control a matrix converter different modulations are possible. To benefit from the new topology the rectifying and inverting vector modulation (RIVM) can be used. It is a complex theory but this article presents a realization in one single programmable logic device. Additionally pulse pattern execution (PWM, commutation strategies and input voltage/current filtering) are situated in the same device. This was possible after the optimization and the reduction of the necessary calculation steps. This new solution works without an extra micro-controller or a digital signal processor (DSP). It allows great reduction in costs of matrix converter controls implementation and increases the performance.
Biological Consequences of Thrombin Receptor Deficiency in Mice (1996)

The thrombin receptor (ThrR) is a membrane-bound, G-protein-coupled receptor for the serine protease thrombin. This receptor is expressed in a wide variety of cells and tissues, and elicits a range of physiological responses associated with tissue injury, inflammation, and wound repair. To achieve a better understanding of the physiological role of the ThrR, we have employed homologous recombination to create mice with a disrupted ThrR gene. Following heterozygous (+/-) intercrosses, a total of 351 surviving offspring were genotyped. Only 7% of these offspring were identified as homozygous (-/-) for the disrupted allele, indicating a profound effect on embryonic development. Paradoxically, adult ThrR-/- mice appeared to be normal by anatomical and histological analysis, including their platelet number and function. Similarly, ThrR deficiency had no detectable effect in adult ThrR-/- mice on basal heart rate, arterial blood pressure, vasomotor responses to angiotensin II and acetycholine, and coagulation parameters, even though the ThrR is expressed in many cardiovascular tissue types. In addition, the loss of ThrR function in the peripheral vasculature of adult ThrR-/- mice was confirmed by the absence of various standard hemodynamic effects of the ThrR-activating peptides SFLLRN-NH2 and TFLLRNPNDK-NH2. Our results indicate that ThrR deficiency has a strong impact on fetal development; however. ThrR-/- mice that proceed to full development display surprisingly little change in phenotype compared to the wild-type.
Evaluation of the stress-optical coefficients of transparent solid plates using interferometry (1979)

A theoretical analysis that leads to a method for the evaluation of the stress-optical coefficient. If a monochromatic collimated light beam impinges at the tip of the crack, of a plate which is under stress the light rays are deviated in such a way that they form two caustic surfaces, the transmitted and the reflected. The observable quantity is the cross section of this surface with an opaque screen which is of an almost circular shape called briefly caustic. While loading of the specimen with no crack, a displacement of fringes is observed due to the change in optical path. The ratio of the size of the two caustics as they are observed on the screen and the number of displaced fringes per unit of applied stress are the only parameters encountered in the presented analysis in contrast to other methods that require additional knowledge of the elastic parameters of the solid. Experimental data taken in accordance with this method verify its validity.
Role of the second extracellular loop of adenosine receptors in agonist and antagonist binding. Analysis of chimeric A1/A3 adenosine receptors. (1994)

Adenosine receptor (AR) agonists and antagonists are approximately 100-fold and 100,000-fold, respectively, more potent at the bovine A1AR as compared to the rat A3AR. To determine regions of ARs involved in ligand recognition, chimeric receptors composed of bovine A1AR and rat A3AR sequence were constructed and their ligand binding properties examined following expression in COS-7 cells. Substitutions of the second extracellular loop or a region encompassing transmembrane domains 6 and 7 of the A1AR into the A3AR resulted in enhanced affinities of both agonists and antagonists compared to wild-type A3AR. The region of the second extracellular loop of the A1AR responsible for this effect was identified as the distal eleven amino acids of the loop. Replacement of this segment of the A3AR with that of the A1AR in combination with the regions encompassing transmembrane domains 6 and 7 resulted in a 50,000-fold increase in the Kd for antagonist radioligand, [3H]1,3-dipropyl-8- cyclopentylxanthine. Agonist affinity at this chimeric was over 100-fold greater than that displayed by wild-type A3AR. Thus, multiple regions of ARs including a segment of the second extracellular loop are involved in ligand recognition, and considerable overlap exists in structural features required for agonist and antagonist binding.
Ultralow Thermal Conductivity in Disordered, Layered WSe <sub>2</sub> Crystals (2006)

The cross-plane thermal conductivity of thin films of WSe2 grown from alternating W and Se layers is as small as 0.05 watts per meter per degree kelvin at room temperature, 30 times smaller than the c-axis thermal conductivity of single-crystal WSe2 and a factor of 6 smaller than the predicted minimum thermal conductivity for this material. We attribute the ultralow thermal conductivity of these disordered, layered crystals to the localization of lattice vibrations induced by the random stacking of two-dimensional crystalline WSe2 sheets. Disordering of the layered structure by ion bombardment increases the thermal conductivity.
Enzymatic Continuous Flow Synthesis of Thiol‐Terminated Poly(δ‐Valerolactone) and Block Copolymers (2018)

Thiol-terminated poly(δ-valerolactone) is directly synthesized via enzymatic 6-mercapto-1-hexanol initiated ring-opening polymerization in both batch and microreactor. By using Candida antartica Lipase B immobilized tubular reactor, narrowly dispersed poly(δ-valerolactone) with higher thiol fidelity is more efficiently prepared in contrast to the batch reactor. Moreover, the integrated enzyme packed tubular reactor system is established to perform the chain extension experiments. Thiol-terminated poly(δ-valerolactone)-block-poly(ε-caprolactone) and poly(ε-caprolactone)-block-poly(δ-valerolactone) are easily prepared by modulating the monomer introduction sequence.
Caddisfly Inspired Phosphorylated Poly(ester urea)-Based Degradable Bone Adhesives (2016)

Bone and tissue adhesives are essential in surgeries for wound healing, hemostasis, tissue reconstruction, and drug delivery. However, there are very few degradable materials with high adhesion strengths that degrade into bioresorbable byproducts. Caddisfly adhesive silk is interesting due to the presence of phosphoserines, which are thought to afford adhesive properties. In this work, phosphoserine-valine poly(ester urea) copolymers with 2% and 5% phosphoserine content were synthesized to mimic caddisfly adhesive silk. Significantly, the materials are ethanol soluble and water insoluble, making them clinically relevant. Their physical properties were quantified, and the adhesion properties were studied on aluminum and bovine bone substrates before and after cross-linking with Ca(2+) ions. The adhesive strength of the phosphorylated copolymer on a bone substrate after cross-linking with Ca(2+) was 439 ± 203 kPa, comparable to commercially available PMMA bone cement (530 ± 133 kPa).
E-band Nd^3+ amplifier based on wavelength selection in an all-solid micro-structured fiber (2017)

A Nd<sup>3+</sup> fiber amplifier with gain from 1376 nm to 1466 nm is demonstrated. This is enabled by a wavelength selective waveguide that suppresses amplified spontaneous emission between 850 nm and 1150 nm. It is shown that while excited state absorption (ESA) precludes net gain below 1375 nm with the exception of a small band from 1333 nm to 1350 nm, ESA diminishes steadily beyond 1375 nm allowing for the construction of an efficient fiber amplifier with a gain peak at 1400 nm and the potential for gain from 1375 nm to 1500 nm. A peak small signal gain of 13.3 dB is measured at 1402 nm with a noise figure of 7.6 dB. Detailed measurements of the Nd<sup>3+</sup> emission and excited state absorption cross sections suggest the potential for better performance in improved fibers. Specifically, reduction of the fiber mode field diameter from 10.5 µm to 5.25 µm and reduction of the fiber background loss to <10 dB/km at 1400 nm should enable construction of an E-band fiber amplifier with a noise figure < 5 dB and a small signal gain > 20 dB over 30 nm of bandwidth. Such an amplifier would have a form factor and optical properties similar to current erbium fiber amplifiers, enabling modern fiber optic communication systems to operate in the E-band with amplifier technology similar to that employed in the C and L bands.
On shape and the computability of emotions (2012)

We investigated how shape features in natural images influence emotions aroused in human beings. Shapes and their characteristics such as roundness, angularity, simplicity, and complexity have been postulated to affect the emotional responses of human beings in the field of visual arts and psychology. However, no prior research has modeled the dimensionality of emotions aroused by roundness and angularity. Our contributions include an in-depth statistical analysis to understand the relationship between shapes and emotions. Through experimental results on the International Affective Picture System (IAPS) dataset we provide evidence for the significance of roundness-angularity and simplicity-complexity on predicting emotional content in images. We combine our shape features with other state-of-the-art features to show a gain in prediction and classification accuracy. We model emotions from a dimensional perspective in order to predict valence and arousal ratings which have advantages over modeling the traditional discrete emotional categories. Finally, we distinguish images with strong emotional content from emotionally neutral images with high accuracy.
Systematic analysis of intra-superchannel nonlinear crosstalk in flexible grid networks (2014)

Intra-superchannel nonlinear crosstalk affects center subcarriers of multi-carrier superchannels more than the edge subcarriers; its impact on center subcarriers significantly increases with increase of the number of subcarriers. Power pre-emphasis of subcarriers effectively equalizes performance and extends reach by 20%.
Automatic Extraction of Objects of Interest by Minimizing a Local-Global Variational Energy (2006)

Abstract. In this paper, we propose a novel variational energy formulation for automatic extraction of object of interest from images. Traditional variational energy formulation for image segmentation like that in [1] only incorporates local region potentials with a Gaussian distribution on each region. We argue that for segmentation of natural objects, Gaussian mixture model (GMM) needs to be adopted to capture the appearance variation of the objects. Moreover, we introduce a global image data likelihood potential to address the problem that each local region usually contains a portion of incorrectly partitioned pixels during the iterations. By combining it with local region potentials, we obtain more robust and accurate estimation of the foreground& background distributions. The minimization of the proposed local-global energy functional is achieved in two steps: the evolution of the foreground & background boundary curve by level set; and the robust estimation of the foreground& background model by fixed-point iteration called quasisemi-supervised EM, which is particularly suited for the learning problem where some unknown portion of the data are labeled incorrectly. Extensive experimental results including business card extraction, road sign extraction and general object-of-interest segmentation demonstrates the robustness, effectiveness, and efficiency of the proposed approach.
<title>Development of photopolymer/liquid crystal composite materials for dynamic hologram applications</title> (1994)

Switchable holographic gratings are desirable for a wide range of applications in diffractive optics. Liquid crystalline materials look attractive for these devices because of their large field- induced birefringence. The combination of electro-optical liquid crystals with photopolymeric holographic materials offers a unique single system approach to the economical fabrication of switchable holograms. We report on the progress in our development of a novel system where holographic gratings are recorded in a single step process and consist of periodic polymer-dispersed liquid crystal planes. Gratings have been recorded with high diffraction efficiency (approaching 100%) and narrow angular selectivity (<1 degree(s) FWHM). The diffraction efficiency can be controlled electrically or thermally
Beamwidth Optimization for 5G NR Millimeter Wave Cellular Networks: A Multi-armed Bandit Approach (2021)

The use of highly directional antennas in millimeter wave (mmWave) cellular networks necessitates precise beam alignment between a base station (BS) and a user equipment (UE), which requires beam sweeping over a large number of directions and causes high initial access (IA) delay. Intuitively, such delay can be lowered by using wider beams, as fewer directions need to be swept. However, this results in a weak received signal and higher misdetection probability, which in turn increases the IA delay as more rounds of beam sweeping would be required to discover a UE. In this paper, we propose a multi-armed bandit approach for beamwidth optimization in 5G New Radio (NR) mmWave cellular networks. We aim to find the optimal beamwidths at the BS and the UE that minimize the beam sweeping delay for a successful IA. We first formulate the beamwidth optimization problem based on analyzing the interplay among beamwidth, beam sweeping overhead, and misdetection probability. Then, we propose a two-stage solution framework based on a multi-armed bandit approach. In the first stage, an initial solution of the BS beamwidth and the optimal solution of UE beamwidth are derived. In the second stage, each BS learns its optimal beamwidth by solving a multi-armed bandit problem with a Thompson sampling-based algorithm. Our extensive simulation results show that, the proposed algorithms can decrease the IA delay by more than 50% compared to the traditional fixed-beamwidth schemes.
Enzymatic Semisynthesis of Growth Hormone-Releasing Factor and Potent Analogs (1994)

The potential value of enzymes in peptide synthesis is derived from the highly selective nature of these catalysts. Proteolytic enzymes can catalyze regioselective acylations, thereby eliminating the need for side-chain-protecting groups in favorable cases. The rigid stereoselectivity of the proteases ensures optically pure products, even from racemic starting materials. These properties make biocatalysis especially attractive for convergent synthetic strategies employing segment condensations in which racemization is often a concern with conventional stoichiometric coupling reagents. In addition, enzymatic segment condensations can be performed for segments without the side-chain-protecting groups that often create solubility problems and require additional stages of deprotection.
Evaluation of the Combination of Fecal Lactoferrin and Fecal Anti-Saccharomyces Cerevesiae Antibodies To Detect Active Crohnʼs Disease (2007)

Purpose: Prior studies of a quantitative assay for fecal lactoferrin showed high sensitivity and specificity in detecting intestinal inflammation in inflammatory bowel disease (IBD). Prior studies have indicated that an assay to detect fecal antibodies to Saccharomyces cerevesiae (ASCA) may be able to identify patients (pts) with Crohn's disease (CD). We sought to determine the diagnostic utility of a combined analysis to detect both fecal lactoferrin and fecal ASCA in pts evaluated at an IBD clinic. Methods: Between 3/04 and 10/06, pts with known or suspected CD who were undergoing evaluation with colonoscopy +/− small bowel x-ray were offered enrollment. Study subjects provided stool and serum samples within 72 hrs of colonoscopy and these were sent for analysis (quantitative enzyme-linked immunoassay [EIA] for fecal lactoferrin, qualitative EIA for both fecal and serum ASCA, and INOVA serum ASCA IgG). The reference standard was physician global assessment based on colonoscopy, biopsy, and (if available) small bowel x-ray (CT enterography or small bowel follow-through). Results: A total of 69 pts were enrolled (39 active CD, 12 inactive CD, 5 active ulcerative [UC] or indeterminate colitis[IC], and 13 non-IBD conditions). In the active CD group, 6 did not submit stool samples and 3 did not submit serum. Three non-IBD pts and 1 UC/IC pt did not submit serum. See table for comparisons of fecal lactoferrin and fecal/serum ASCA. Fecal lactoferrin was elevated in 33 of 38 pts with active IBD (87%) vs. 17% of inactive CD and 38% non-IBD miscellaneous. Fecal ASCA was detected in both active and inactive CD. Conclusion: Fecal lactoferrin distinguishes active IBD from inactive IBD and miscellaneous GI disorders. Fecal ASCA is present in the majority of CD pts and may aid in distinguishing CD from non-IBD; however, additional studies using a larger number of active UC pts are needed to evaluate the role of fecal ASCA to differentiate UC from CD.Table
Application of Passive Voltage Contrast (PVC) to Dual Beam Focused Ion Beam (FIB) Based Sample Preparation for the Scanning/Transmission Electron Microscope (S/TEM) (2014)

Abstract The modern scanning transmission electron microscope (S/TEM) has become a key technology and is heavily utilized in advanced failure analysis (FA) labs. It is well equipped to analyze semiconductor device failures, even for the latest process technology nodes (20nm or less). However, the typical sample preparation process flow utilizes a dual beam focused ion beam (FIB) microscope for sample preparation, with the final sample end-pointing monitored using the scanning electron microscope (SEM) column. At the latest technology nodes, defect sizes can be on the order of the resolution limit for the SEM column. Passive voltage contrast (PVC) is an established FA technique for integrated circuit (IC) FA which can compensate for this resolution deficiency in some cases. In this paper, PVC is applied to end-pointing cross-sectional S/TEM samples on the structure or defect of interest to address the SEM resolution limitation.