gebhart/patrepeval huggingface dataset:
Special issue to Honor Professor Fred W. McLafferty (1995)

ADVERTISEMENT RETURN TO ISSUEEditorialNEXTSpecial issue to Honor Professor Fred W. McLaffertyMichael L. GrossMichael L. GrossWashington University, St. LouisMore by Michael L. Gross and I. Jonathan AmsterI. Jonathan AmsterUniversity of Georgia, AthensMore by I. Jonathan AmsterCite this: J Am Soc Mass Spectrom 1995, 6, 11, 992Publication Date (Print):November 1, 1995Publication History Published online1 November 1995Published inissue 1 November 1995https://pubs.acs.org/doi/10.1016/S1044-0305(95)90470-0https://doi.org/10.1016/S1044-0305(95)90470-0editorialACS Publications. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views31Altmetric-Citations-LEARN 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 PDF (181 KB) Get e-Alerts
Polymeric Flocculants Prove Most Effective Chemicals for Wellbore Cleanup Operations (1994)

Abstract Upcoming zero discharge regulations, high rig time cost, and low oil prices are motivating the industry to look for faster, more effective displacement that reduce the volume of fluid to dispose and decrease circulation time. A field study conducted in South East Asia showed that more effective displacement can be achieved by adding to the circulating fluid a polymeric flocculant instead of the commonly used surfactants. A laboratory investigation was undertaken to understand the fundamental mechanism governing well bore clean-up. Its conclusions are as follows: under the highly turbulent flow conditions reigning during displacement operations, saltwater cleans metallic surfaces as well as surfactant solutions;polymeric flocculants form larger and stronger aggregates of solids than surfactants which can withstand better the stresses associated with turbulent flow. This improves the sweeping efficiency of the circulating fluid by increasing fluid drag force on the solids.
82‐3: 3. 9‐mm Ultra‐Slim Curved TV Having a Glass Light‐Guide Plate (2017)

Ultra‐slim curved LCD TV with thickness of 3.9 mm was successfully developed by using glass light guide plate (LGP). Since there are many different properties between glass LGP and traditional PMMA LGP, special technical considerations of ultra‐slim curved design such as mechanical and optical characteristics were simulated and analyzed.
Tumor skewing of CD34+ progenitor cell differentiation into endothelial cells (2004)

Tumor production of granulocyte-macrophage colony-stimulating factor (GM-CSF) results in the mobilization of CD34(+) progenitor cells into the peripheral blood and tumor tissue. Using the Lewis lung carcinoma (LLC) model, in vitro studies showed that LLC cells could chemoattract CD34(+) cells predominantly through tumor production of VEGF. Addition of LLC-conditioned medium to CD34(+) cells that were cultured under conditions that support myeloid lineage cells skewed the differentiation of these precursor cells toward endothelial cells expressing CD31 and CD144. This differentiation of CD34(+) cells toward endothelial cells was attributed predominantly to angiopoietin-1 in the tumor-conditioned medium. The CD34(+) cells expressed the angiopoietin receptor Tie-2 and their differentiation into endothelial cells was blocked with neutralizing angiopoietin-1 antibodies. In vivo studies showed that infusion of lacZ(+) CD34(+) cells from the bone marrow of transgenic mice into wild-type mice bearing LLC tumors resulted in the accumulation of lacZ(+) cells within the tumor mass, particularly at the tumor's periphery. That these infused CD34(+) progenitor cells could develop into endothelial cells of the tumor vasculature was supported by their acquisition of the endothelial cell markers CD31 or CD144 within the tumor tissue. These studies demonstrate the capacity of tumor to attract CD34(+) cells to the tumor site and to direct the differentiation of these CD34(+) cells into endothelial cells that can become a component of the tumor vasculature.
Further Studies of β-Eliminations Involving Silicon1 (1948)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFurther Studies of β-Eliminations Involving Silicon1Leo H. Sommer, Donald L. Bailey, and Frank C. WhitmoreCite this: J. Am. Chem. Soc. 1948, 70, 9, 2869–2872Publication Date (Print):September 1, 1948Publication History Published online1 May 2002Published inissue 1 September 1948https://pubs.acs.org/doi/10.1021/ja01189a009https://doi.org/10.1021/ja01189a009research-articleACS PublicationsRequest reuse permissionsArticle Views150Altmetric-Citations75LEARN 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
Tuning the Effective Work Function of Gold and Silver Using ω-Functionalized Alkanethiols: Varying Surface Composition through Dilution and Choice of Terminal Groups (2009)

Thiol-based self-assembled monolayers (SAMs) have been used to tune the effective work function of gold over a range of ca. 1.8 eV via two strategies: (i) the use of ω-functionalized alkanethiols where the tail groups have widely varying electronegativity or (ii) by the creation of two-component SAMs from selected mixtures of methyl-terminated alkanethiols (C16) and alkanethiols fluorinated at the two terminal carbon atoms (C16F2). UV-photoelectron spectroscopy (UPS) was used to monitor changes in effective work function, using shifts in the low kinetic energy edge of these photoemission spectra to quantify the shift in local vacuum level resulting from the interface dipole effect created by the surface modifier. Tail groups on alkanethiol chains varied from −CH3, to −phenyl, −Cl, −Br, and −CF3 or −CF2CF3, which provided a shift in local vacuum level that varied linearly with the calculated molecular dipole moment of the individual modifiers, as observed previously for a more limited range of alkanethiols (J. Phys. Chem. B 2003, 107, 11690). The studies presented here confirm that the intrinsic dipole in the gold−thiolate bond is small (less than 100 meV), whereas the silver−thiolate bond appears to have a strongly polar character, in the direction Ag+−S− (ca. 900 meV). The use of a simple point dipole model to rationalize these apparent shifts in vacuum level was further explored using SAMs derived from various mixtures of C16 and C16F2. The low kinetic energy edge in the UV-photoemission spectra and the effective work function are observed to increase monotonically in energy with increasing C16F2 coverage, confirming that little surface segregation occurs in these self-assembled monolayers over a wide concentration range.
A Density based Priority Queue Strategy to Evaluate Iceberg Queries Efficiently using Compressed Bitmap Indices (2013)

In particular, iceberg query is a special class of aggregation query that computes aggregated values upon user interested threshold (T).The bitmap index is a common data structure for fast retrieval of matching tuples from data base table. These resultant tuples are useful to compute aggregations such as SUM, COUNT, AVG, MIN, MAX, and RANK. In this paper, we propose a density based bitmap pruning strategy to evaluate iceberg queries efficiently using compressed bitmap indices. The strategy prioritizes the vectors to be enter in to priority queue by allowing high density of 1's count that achieve optimal pruning effect. Extensive experimentation demonstrates our proposed approach is much more efficient than existing strategy.
Etiologic Diagnosis of Infective Endocarditis by Broad-Range Polymerase Chain Reaction: A 3-Year Experience (2003)

We analyzed surgically resected endocardial specimens from 49 patients by broad-range PCR. PCR results were compared with (1) results of previous blood cultures, (2) results of culture and Gram staining of resected specimens, and (3) clinical data (Duke criteria). Molecular analyses of resected specimens and previous blood cultures showed good overall agreement. However, in 18% of patients with sterile blood cultures, bacterial DNA was found in the resected materials. When data from patients with definite or rejected cases of infective endocarditis (IE) were included, the sensitivity, specificity, and positive and negative predictive values of broad-range PCR were 82.6%, 100%, 100%, and 76.5%, respectively, overall, and 94.1%, 100%, 100%, and 90%, for cases of native valve endocarditis. The sensitivity, specificity, and positive and negative predictive values of culture of resected specimens from patients with native valve endocarditis were 17.6%, 88.9%, 75%, and 36.4%. We recommend broad-range PCR of surgically resected endocardial material in cases of possible IE, in cases of suspected IE in which blood cultures are sterile, and in cases in which organisms grow in blood cultures but only Duke minor criteria are met. We propose to add molecular techniques to the pathologic criteria of the Duke classification scheme.
64Cu-DOTATATE PET for Neuroendocrine Tumors: A Prospective Head-to-Head Comparison with 111In-DTPA-Octreotide in 112 Patients (2015)

With these results, we demonstrate that (64)Cu-DOTATATE is far superior to (111)In-DTPA-OC in diagnostic performance in NET patients. Therefore, we do not hesitate to recommend implementation of (64)Cu-DOTATATE as a replacement for (111)In-DTPA-OC.
Influencing passenger egress to reduce congestion at rail stations (2015)

As rail station patronage levels increase, so too does the load on the entire railway system. The higher passenger densities exacerbate local egress issues and thus adversely affect dwell time and subsequently punctuality, along with the passenger experience. Devices such as barriers are regularly used to influence passenger egress. However, their use is typically limited to special events; where perhaps a single influence-objective is intended on a relatively uniform passenger demographic. This limitation precludes such devices usefulness for daily operations; where potentially multiple influence-objectives, which potentially change regularly, exists. Furthermore, it is reasonable to expect a considerably less uniform passenger demographic which perhaps includes passengers that are less receptive to particular influence strategies. This paper presents an exploration of components of a robotic system that is responsive to real time person behaviours and operator's needs. Specifically, details of our methods for identification of the passenger demographic groups and passenger egress influencing are presented along with results from two studies. The first study was conducted at Townhall Station Sydney and explored our robotic system's ability to reliably identify the passenger demographic of individual passengers in real time. The ability of our robotic system to influence real time egress of real in-transit passengers in situ, and the ability to responsively moderate influence-objective based on observed characteristics was explored in the second study which was co-located at Perth Station Perth and the University of Technology Sydney. Finally, this paper discusses how this predictable influence of passenger egress can potentially be leveraged to benefit operations.
Vasopressin, but Not Fluid Resuscitation, Enhances Survival in a Liver Trauma Model with Uncontrolled and Otherwise Lethal Hemorrhagic Shock in Pigs (2003)

Vasopressin, but not fluid resuscitation or saline placebo, ensured survival with full recovery in this liver trauma model with uncontrolled and otherwise lethal hemorrhagic shock in pigs.
Influence of transverse magnetic fields and depletion of working levels on the nonlinear resonance Faraday effect (2003)

The nonlinear resonance Faraday effect is studied under the condition of coherent population trapping in 87Rb vapor at the D 1-line F=2→F′=1 transition. The influence of transverse magnetic fields on the nonlinear optical Faraday rotation is studied. For the transverse fields perpendicular to the electromagnetic-wave polarization, a simple theoretical model is proposed, which is in good agreement with experimental data. The optimal intensity providing the maximum sensitivity is found based on the results obtained. The influence of working-level depletion on the parameters of Faraday rotation in open systems is studied experimentally and theoretically. The system was closed in the experiment by using an additional laser to increase the sensitivity and extend the dynamic range of measured fields. The importance of compensating for the depletion in the presence of spurious magnetic fields is shown; in particular, the sensitivity was enhanced by a factor of 50 in experiments with a buffer gas.
A 14-bit 20-MS/s Pipelined ADC With Digital Distortion Calibration (2006)

A new digital distortion calibration technique is demonstrated in a 14-bit 20-MS/s pipelined analog-to-digital converter (ADC). Calibration parameters are obtained in a way similar to conventional digital gain calibration. The prototype ADC has been fabricated in a 0.18-mum CMOS process and consumes 33.7 mW at 2.8 V. Using the proposed calibration method, a 15-dB improvement of the third-order harmonic rejection is achieved. The measured SNDR and SFDR are 71.6 and 82.3 dB, respectively
Improved Utilization of Pond Carrying Capacity by Increasing Initial Stocking Rates and Subsequent Stock Division1 (1997)

Abstract Fingerling channel catfish Ictaturus punctarus were stocked into eight 0.04‐ha ponds at 12,500 fishlha (treatment 1) and 50,000 fish/ha (treatment 2) with four ponds per treatment. At the end of of phase I (59 d) 50% of the fish were removed from each of the ponds in treatment 2 and divided equally into two ponds, forming treatment 3 (eight ponds at a density of 12,500 fish/ha). The remaining fish in treatment 2 (25,000 fish/ha) were maintained in the original ponds until the end of phase II (36 d). At this time, the fish were removed and equally divided at a density of 12,500 fish/ha into separate ponds. These ponds were continued to be denoted as treatment 2. All fish were grown for a total of 188 d. Production characteristics between treatments were compared at phases and at the end of the 188 d. There was no significant difference in feed conversion ratios due to treatment. The individual weights of the fish were higher in treatment I, but the difference occurred only in phase I. Size variabilities in treatments 2 and 3 were also higher than in treatment 1, which may cause a decrease in the percentage of marketable fish. Although there were some adverse effects due to the initial high stocking densities, overall pond production was higher in treatments 2 and 3. Treatment 2 had a daily net production of 49.9 ± 3.43 kg/ha and treatment 3 had 44.6 ± 3.81 kg/ha per d, compared to treatment 1 with only 32.4 ± 1.06 kg/ha per d (mean ± SD).
Ensemble Gaussian Processes for Adaptive Autonomous Driving on Multi-friction Surfaces (2023)

Driving under varying road conditions is challenging, especially for autonomous vehicles that must adapt in real-time to changes in the environment, e.g., rain, snow, etc. It is difficult to apply offline learning-based methods in these time-varying settings, as the controller should be trained on datasets representing all conditions it might encounter in the future. While online learning may adapt a model from real-time data, its convergence is often too slow for fast varying road conditions. We study this problem in autonomous racing, where driving at the limits of handling under varying road conditions is required for winning races. We propose a computationally-efficient approach that leverages an ensemble of Gaussian processes (GPs) to generalize and adapt pre-trained GPs to unseen conditions. Each GP is trained on driving data with a different road surface friction. A time-varying convex combination of these GPs is used within a model predictive control (MPC) framework, where the model weights are adapted online to the current road condition based on real-time data. The predictive variance of the ensemble Gaussian process (EGP) model allows the controller to account for prediction uncertainty and enables safe autonomous driving. Extensive simulations of a full scale autonomous car demonstrated the effectiveness of our proposed EGP-MPC method for providing good tracking performance in varying road conditions and the ability to generalize to unknown maps.
Polarization-Resolved Extreme Ultraviolet Second Harmonic Generation from LiNbO$_3$ (2021)

Second harmonic generation (SHG) spectroscopy ubiquitously enables the investigation of surface chemistry, interfacial chemistry, as well as symmetry properties in solids. Polarization-resolved SHG spectroscopy in the visible to infrared regime is regularly used to investigate electronic and magnetic order through their angular anisotropies within the crystal structure. However, the increasing complexity of novel materials and emerging phenomena hampers the interpretation of experiments solely based on the investigation of hybridized valence states. Here, polarization-resolved SHG in the extreme ultraviolet (XUV-SHG) is demonstrated for the first time, enabling element-resolved angular anisotropy investigations. In noncentrosymmetric LiNbO_{3}, elemental contributions by lithium and niobium are clearly distinguished by energy dependent XUV-SHG measurements. This element-resolved and symmetry-sensitive experiment suggests that the displacement of Li ions in LiNbO_{3}, which is known to lead to ferroelectricity, is accompanied by distortions to the Nb ion environment that breaks the inversion symmetry of the NbO_{6} octahedron as well. Our simulations show that the measured second harmonic spectrum is consistent with Li ion displacements from the centrosymmetric position while the Nb─O bonds are elongated and contracted by displacements of the O atoms. In addition, the polarization-resolved measurement of XUV-SHG shows excellent agreement with numerical predictions based on dipole-induced SHG commonly used in the optical wavelengths. Our result constitutes the first verification of the dipole-based SHG model in the XUV regime. The findings of this work pave the way for future angle and time-resolved XUV-SHG studies with elemental specificity in condensed matter systems.
Load sharing based on popularity in distributed video on demand systems (2003)

In recent years, there has been an increasing interest in video on demand (VoD) systems. We study a distributed VoD system in which the videos are replicated according to their popularity. We present an algorithm to share the load in such a system efficiently and an analytical model that captures the performance of this algorithm, which we validate through simulations. This research shows that popularity is an essential parameter which can save storage without reducing performance by just replicating a few popular videos in all the servers.
ChemInform Abstract: Reductive Beckmann′s Type Fragmentation of α‐Amino Oximes by Sodium Borohydride: A New Synthetic Pathway to ω‐Amino Nitriles. (1994)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
The synthesis of l‐alkyl‐1,4‐dihydro‐4‐quinolone‐2‐carboxylic acids (1978)

Abstract A general method tor the preparation of 1,4‐dihydro‐4‐quinolone‐2‐carboxylic acids, especially those which carry alkyl substituents on the ring N ‐atom, is described.
The pH Inside a pH-Sensitive Gel Swollen in Aqueous Salt Solutions: Poly(N-vinylimidazole) (2009)

The pH inside a swollen polyelectrolyte network is calculated through a simple model, based on Donnan equilibrium and balance of mobile ions, extended to include the presence of a supporting electrolyte (salt) in the solution that swells the particle. This pH inside the gel, although needed to characterize the ionization properties of the polyelectrolyte, is generally not accessible to direct measurement. The main advantage of our model is that it is free from any simplification concerning the pKa of the ionizable groups. A common univalent anion is assumed for the acid and salt. The model was applied to chemically cross-linked poly(N-vinylimidazole) (PVI) immersed in acidic aqueous baths containing variable concentrations of HCl and NaCl as supporting electrolyte. The imidazole units are basic and become protonated by the acid, thus changing the pH of the initial bath. The data needed for the calculation of the proton concentration inside the gel, the degree of ionization, and the pKa of the polyelectrolyte are: polymer concentration, pH and salt concentration in the initial solution, and pH in the bath at equilibrium. All of them can be determined experimentally by a batch method, where the polymer is immersed in a different pot for each starting pH and salt concentration. It was thus found that in salt free solutions the pH inside the gel is several units higher than the pH in the external bath at equilibrium, but this difference between internal and external pH faints with added salt. The intrinsic pKa of PVI, determined from the pH in the gel, is slightly higher than the pKa of the model molecule, for salt free solutions, but it is lower with added salt (possibly due to the formation of a hydrogen bond between two imidazole units and its disruption by chloride). It was concluded that the pH inside the polymer must be employed instead of the pH outside, in order to calculate pKa, not only for a swollen polymer network, but also for a dissolved coil.
Brain microstructural changes in stroke patients at subacute/chronic stages by mean of advanced diffusion MRI: a longitudinal study (2023)

This study characterises microstructural changes in stroke lesions using NODDI and WMTI, two advanced diffusion MRI techniques, and compares their ability to detect WM alterations on the ipsi-lesional and contralesional sides of 12 patients scanned 2 weeks, 1 month and 3 months after onset. Region-of-interest analysis showed that ODI and FWF from NODDI were significantly altered at the lesion. Significant changes were also found in the WMTI parameters of several ipsi-lesional white matter tracts. Our prospective analysis suggests that the application of enhanced dMRI methods such as NODDI and WMTI can help to further comprehend the biophysical mechanism behind ischemia.