gebhart/patrepeval huggingface dataset:
Regioselective Opening of Terminal Epoxides with 2-(Trialkylsilyl)allyl Organometallic Reagents (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRegioselective Opening of Terminal Epoxides with 2-(Trialkylsilyl)allyl Organometallic ReagentsLarry E. Overman and Paul A. RenhoweCite this: J. Org. Chem. 1994, 59, 15, 4138–4142Publication Date (Print):July 1, 1994Publication History Published online1 May 2002Published inissue 1 July 1994https://pubs.acs.org/doi/10.1021/jo00094a026https://doi.org/10.1021/jo00094a026research-articleACS PublicationsRequest reuse permissionsArticle Views544Altmetric-Citations35LEARN 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-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Practical Power-Balanced Non-Orthogonal Multiple Access (2017)

This paper is a theoretical-plus-experimental investigation of practical 5G strategies for power-balanced non-orthogonal multiple access (NOMA). By allowing multiple users to share the same time and frequency, NOMA can scale up the number of served users and increase spectral efficiency compared with existing OMA. Conventional NOMA schemes with successive interference cancellation (SIC) do not work well when users with comparable received powers transmit together. To allow power-balanced NOMA (more exactly, near power-balanced NOMA), this paper investigates a new NOMA architecture, named network-coded multiple access (NCMA). A distinguishing feature of NCMA is the joint use of physical-layer network coding (PNC) and multiuser decoding to boost NOMA throughputs. We first show that a simple NCMA architecture in which all users use the same modulation, referred to as rate-homogeneous NCMA, can achieve substantial throughput improvement over SIC-based NOMA under near power-balanced scenarios. Then, we put forth a new NCMA architecture, referred to as rate-diverse NCMA, in which different users may adopt different modulations commensurate with their relative SNRs. A challenge for rate-diverse NCMA is the design of a channel-coded PNC system. This paper is the first attempt to design channel-coded rate-diverse PNC. Experimental results on our software-defined radio prototype show that the throughput of rate-diverse NCMA can outperform the state-of-the-art rate-homogeneous NCMA by 80%. Overall, rate-diverse NCMA is a practical solution for near power-balanced NOMA.
Which electrode? A comparison of four endoscopic methods of electrocoagulation in experimental bleeding ulcers. (1984)

Several inexpensive endoscopic methods of electrocoagulation have been advocated for treatment of gastrointestinal haemorrhage. We compared four types of electrode: dry monopolar - Cameron Miller (M), liquid monopolar - Storz (L), bipolar - Bicap ACMI (B), and heater probe - Seattle (H). The electrical and thermal properties of these probes were studied using computerised monitoring of energy deposition and their efficacy and safety was tested in a randomised study in 140 experimental canine gastric ulcers. At optimal pulse settings 20J (M), 70J (L), 17J (B), 15J (H), effective haemostasis was achieved in all ulcers, the mean number of pulses being M5, L6, H6 and B11, the first three requiring significantly (p less than 0.01) less pulse than B. Relative safety of the electrodes was assessed by comparing the incidence of full thickness damage at histology: B24%, H20%, L58% and M69%; B and H proving significantly (p less than 0.01) safer than L and M. Sticking was assessed as H greater than B greater than M much greater than L. Insensitivity to extreme angulation and force of application was assessed as L greater than B greater than M (H is preset). Of the two safer electrodes the heater probe was more effective than the bipolar probe. Despite its greater tendency to stick than the other devices, the heater probe appeared the most promising of the endoscopic electrodes tested.
Ceramic Matrix Composite as Liners for Improved Ablative Chambers (2009)

Among the various approaches used for cooling the walls of a combustion chamber, ablative cooling is a simple and reliable solution. In that case, in order to reduce changes in throat geometry, an insert is usually used in that region. A proposed alternative is to use advanced ceramic matrix composite liners which are inserted throughout the thrust chamber in order to allow higher wall temperatures than ablatives with greatly reduced erosion rates. This paper details the design of a proof-of-concept 2200 N (500 lbf) thrust LOX/ethanol rocket engine. A Cf/SiCm ceramic matrix composite is used as liner in the chamber and throat for maintaining the combustion chamber internal dimensions. The remainder of the nozzle is made from a typical silica-phenolic ablative. Film cooling is added to maintain the C/SiC liner below 1800⁰C. The aluminum injector features a row of 24 split triplets and 24 film cooling orifices. A successful static fire test of the engine was conducted in November 2008, demonstrating a total burn duration of 33 seconds without significant erosion of the liner while significant ablation was noticed at the liner/ablative transition in the nozzle. The test demonstrated the viability of the concept for improving performance of ablative rocket engines. Future studies will concentrate on transitioning to LOX/methane propellants and reducing required ablative thickness and film cooling. This approach has the potential for improved performance of future ablative engines, such as the lunar ascent main engine now in development for NASA.
Highly Sensitive Small Hydrophone with Built-in Stealth Preamplifier (2022)

The compromise between the sensitivity and smallness of a hydrophone can be eased by a preamplifier directly connected to the piezoelectric element of the hydrophone. However, the acoustic reflection by the preamplifier right next to the element may degrade the pulse response of the hydrophone. The behavior of an ultrasonic pulse, incident to the hydrophone, was numerically simulated using PZFlex, and the signal amplitude detected by the PDVF piezoelectric film was calculated. The result predicts that a highly sensitive small hydrophone can be achieved with a built-in preamplifier by giving acoustical stealth characteristics to the preamplifier.
Transitioning From Single to Multiple Herbicide‐Resistant Crops (2010)

This chapter contains sections titled: Introduction The First HR Crops GR Crops Other Mechanisms That Can Be Stacked with Glyphosate Resistance Summary References
Fast and practical instruction-set randomization for commodity systems (2010)

Instruction-set randomization (ISR) is a technique based on randomizing the "language" understood by a system to protect it from code-injection attacks. Such attacks were used by many computer worms in the past, but still pose a threat as it was confirmed by the recent Conficker worm outbreak, and the latest exploits targeting some of Adobe's most popular products. This paper presents a fast and practical implementation of ISR that can be applied on currently deployed software. Our solution builds on a binary instrumentation tool to provide an ISR-enabled execution environment entirely in software. Applications are randomized using a simple XOR function and a 16-bit key that is randomly generated every time an application is launched. Shared libraries can be also randomized using separate keys, and their randomized versions can be used by all applications running under ISR. Moreover, we introduce a key management system to keep track of the keys used in the system. To the best of our knowledge we are the first to apply ISR on truly shared libraries.
Using the Mass Ratio to Induce Band Gaps in a 1D Array of Nonlinearly Coupled Oscillators (2012)

A one dimensional system of nonlinearly coupled magnetic oscillators has been studied. After deriving the equations of motion for each oscillator, the system is linearized about a stable equilibrium and studied using an assumed solution form for a traveling wave. Wave propagation and attenuation regions are predicted by reducing the system of equations to a standard eigenvalue problem. Through evaluating these equations across the entire irreducible Brillouin zone, it is determined that when the masses of each oscillator are identical, the entire frequency range of the system is a propagation zone. By varying the masses comprising a unit cell, band gaps are observed. It is shown that the mass ratio can be used to guide both the size and location of these band gaps. Numerical simulations are performed to support our analytical findings.
Cellule déphaseuse 3-bit pour les antennes réseaux réflecteurs à double polarisation linéaire (2013)

National audience
Problems (2000)

Ho-joo Lee, Razvan Tudoran, Chi Hin Lau, Anthony A. Ruffa, Hassan A. Shah Ali, Erwin Just, Norman Schaumberger, T. S. Michael, William P. Wardlaw, SMSU Problem Solving Group, Jerrold W. Grossman, Hoe-Teck Wee, Herbert Gulicher, Daniele Donini, Western Maryland College Problems Group, SUNY Oswego Problem Group, David M. Bloom, George T. Gilbert, Michael Reid, Problems, Mathematics Magazine, Vol. 73, No. 4 (Oct., 2000), pp. 321-329
Reduction of Ge-on-Si waveguide propagation loss by laser and hydrogen annealing (2023)

Germanium-on-Silicon (Ge-on-Si) platform has been demonstrated as an excellent candidate for mid-infrared photonics applications, including on-chip mid-infrared spectroscopy and biochemical sensing. However, this platform is often saddled by high propagation loss due to a combination of threading dislocation defects at the Ge/Si interface, absorption in the silicon for λ &lt; 8 μm, and surface scattering due to sidewall roughness. This work investigates the effects on loss reduction through different annealing techniques on Ge-on-Si waveguides fabricated using CMOS-compatible processes. We explore the use of local laser annealing at waveguide sidewalls, whereby the fluence was varied. A non-local annealing technique in hydrogen ambient was also employed as comparison. The propagation losses for wavelengths, ranging from λ = 5 μm to λ = 11 μm, were systematically characterized by fabricating waveguide and grating coupler structures on the same chip. Cutback measurements were performed by varying the waveguide length (of the same width) from L = 1 mm to L = 4 mm. Both hydrogen and laser annealing experiments show marked reduction in the propagation loss, by up to 27% and 46% respectively. This finding paves the way for post-processing techniques to reduce propagation loss in Ge-on-Si platform, which will enable various on-chip mid-IR applications in the future.
ChemInform Abstract: Cu(OTf)2‐Catalyzed Biginelli Type Condensation of Aldehydes, β‐Keto Esters and Carbamates: Synthesis of 3,4‐Dihydro[1,3]oxazin‐2‐ones. (2008)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 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.
Directional Fluorescence Emission by Individual V-Antennas Explained by Mode Expansion (2014)

Specially designed plasmonic antennas can, by far-field interference of different antenna elements or a combination of multipolar antenna modes, scatter light unidirectionally, allowing for directional light control at the nanoscale. One of the most basic and compact geometries for such antennas is a nanorod with broken rotational symmetry, in the shape of the letter V. In this article, we show that these V-antennas unidirectionally scatter the emission of a local dipole source in a direction opposite the undirectional side scattering of a plane wave. Moreover, we observe high directivity, up to 6 dB, only for certain well-defined positions of the emitter relative to the antenna. By employing a rigorous eigenmode expansion analysis of the V-antenna, we fully elucidate the fundamental origin of its directional behavior. All findings are experimentally verified by measuring the radiation patterns of a scattered plane wave and the emission pattern of fluorescently doped PMMA positioned in different regions around the antenna. The fundamental interference effects revealed in the eigenmode expansion can serve as guidelines in the understanding and further development of nanoscale directional scatterers.
Electro-optic response of the anticlinic, antiferroelectric liquid-crystal phase of a biaxial bent-core molecule with tilt angle near 45∘ (2012)

We describe the unusual electro-optic response of a biaxial bent-core liquid crystal molecule that exhibits an anticlinic, antiferroelectric smectic phase (Sm-C(A)P(A)) with a molecular tilt angle close to 45°. In the ground state, the sample shows very low birefringence. A weak applied electric field distorts the antiferroelectric ground state, inducing a small azimuthal reorientation of the molecules on the tilt cone. This results in only a modest increase in the birefringence but an anomalously large (∼40°) analog rotation of the extinction direction. This unusual electro-optic response is shown to be a consequence of the molecular biaxiality.
On K-Means Cluster Preservation Using Quantization Schemes (2009)

This work examines under what conditions compression methodologies can retain the outcome of clustering operations. We focus on the popular k-means clustering algorithm and we demonstrate how a properly constructed compression scheme based on post-clustering quantization is capable of maintaining the global cluster structure. Our analytical derivations indicate that a 1-bit moment preserving quantizer per cluster is sufficient to retain the original data clusters. Merits of the proposed compression technique include: a) reduced storage requirements with clustering guarantees, b) data privacy on the original values, and c) shape preservation for data visualization purposes. We evaluate quantization scheme on various high-dimensional datasets, including 1-dimensional and 2-dimensional time-series (shape datasets) and demonstrate the cluster preservation property. We also compare with previously proposed simplification techniques in the time-series area and show significant improvements both on the clustering and shape preservation of the compressed datasets.
Enhancement of the chemical resistance of nitrile rubber by direct fluorination (2003)

Abstract Nitrile rubber (NBR), poly(acrylonitrile‐ co ‐butadiene) or NBR packers, are used to seal oil‐well tubing, where they often come into contact with ZnBr 2 brines at high temperatures and pressures. Under these conditions, NBR exhibits accelerated chemical degradation, which results in embrittlement and cracking. Although alternative fluoropolymers exhibit excellent chemical resistance, their strength is less than NBR, and replacement of the usual gasket materials with fluoroelastomers is expensive. We have demonstrated that a fluoropolymer surface on a nitrile elastomer provides the necessary chemical resistance while the elastomer retains strength. This can be achieved by direct fluorination, a rather easy and inexpensive process. Samples of NBR O‐rings were fluorinated by exposure to F 2 and F 2 /HF mixtures at various temperatures. Although fluorination by F 2 produced the desired fluoropolymer layer, fluorination by F 2 /HF (hydrofluoric acid) mixtures gave a smoother fluorinated layer at lower temperatures and shorter reaction times. Elemental analysis showed that the fluorinated layer eliminated ZnBr 2 diffusion into the NBR polymeric matrix. Surface fluorination also significantly retarded the loss of the mechanical properties of NBR when it was exposed to zinc bromide fluid. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 971–979, 2003
Joint Speech-Text Embeddings with Disentangled Speaker Features (2023)

This paper presents a novel model architecture for speech processing that takes advantage of a joint speech-text embedding space and disentangled speaker features. Here unsupervised representation learning extracts latent features from the input without labels which results in task-agnostic, but information-entangled embeddings. On the other hand, a unified embedding space of speech and text aims to leverage acoustics and semantic knowledge from the two modalities, respectively. The model was trained on 4 speakers from the CMU Arctic dataset and evaluated on three downstream tasks: speaker recognition, automatic speech recognition (ASR), and text-to-speech (TTS). Results show 96.87% speaker classification accuracy, 11.57% Word Error Rate, and 8.91 Mel Cepstral Distortion mean on the evaluation set.
Bedside chest radiography as part of a postcardiac surgery critical care pathway: A means of decreasing utilization without adverse clinical impact (2000)

Objective: To evaluate the use of bedside chest radiography and patient outcome before and after implementation of a cardiac surgery critical care pathway that included guidelines for bedside radiography. Design: A cohort observational study. Setting: A university hospital in the midwest. Patients: Three groups, of 100 patients each, undergoing cardiac surgery in 1990, 1991, and 1995. Intervention: Introduction of a critical care pathway. Measurements: Medical records were retrospectively reviewed in three groups of 100 patients each: before the introduction of the critical care pathway; 2 months after introduction of the pathway in 1991; and 4 yrs after introduction in 1995. Data were analyzed to determine operative risk for each group. Subsequent analyses determined bedside radiography use, total length of hospital stay, and patient outcome (mortality rate, complications requiring intervention, and reoperation) during hospitalization and at outpatient follow-up 15-30 days postdischarge. Results: Total length of hospital stay was shorter for the 1995 group (7.6 ± 6.6 days) compared with other groups (prepathway, 11.1 ± 10.3 days; 1991 postpathway, 10.2 ± 9.6 days;p< .05). The mean numbers of radiographs per patient were as follows: prepathway, 5.1; 1991 postpathway, 5.2; and 1995 postpathway, 3.3. The mean number of radiographs in the 1995 group was significantly lower (p= .02). More patients had the proposed number of two bedside radiographs described in the pathway in the 1995 group compared with the other groups (prepathway,p< .0001; the two-month postpathway group,p= .01). Twenty-three malpositioned catheters/tubes were found in the prepathway and 1991 groups compared with 11 in the 1995 group (p= .02). No statistically significant difference was found in inpatient complications (mediastinal bleeding, pneumothoraces, and pleural effusions), postdischarge complications, reoperations, or mortality rate. Conclusion: Introduction of a critical care pathway can decrease the use of bedside radiography without adversely affecting near-term patient outcomes.
Prolyl‐isomerase Pin1 controls normal and cancer stem cells of the breast (2014)

A typesetting error led to the deletion of the Y-axis label in Figure 1C. The label should have read “CD24,” and the correct figure is provided below. An author error resulted in the mislabeling of one of the data series in Supplementary Figure S9D. The blue label inside the Kaplan-Meier graphic should read “NDT signature low” instead of “NDT signature high.” The correct Supplementary Figure S9D is provided here. We apologize for any confusion these errors may have caused. Figure 1. Supplementary Figure S9.
UV Direct Write Metal Enhanced Redox (MER) Domain Engineering for Realization of Surface Acoustic Devices on Lithium Niobate (2014)

A new and highly versatile domain patterning method—ultraviolet direct write metal enhanced redox (UV direct write MER)—achieves deep domains with practically no thermally‐induced damage on the surface of lithium niobate crystals. In UV direct write MER, after coating with a thin layer of chromium, the domain inversion is generated by a redox process induced in the crystal by illumination with high intensity UV in an ambient dry nitrogen atmosphere. This new technique enables the fabrication of practical piezoelectric acoustic superlattice structures on 128° YX‐cut LiNbO 3 , the most widely used crystal cut for surface acoustic wave applications. For example, UV direct write MER was used to form an acoustic superlattice 128° YX structure that in turn enabled the generation of surface acoustic waves of sufficient strength to develop fluid flow within a droplet of water, demonstrating its potential in practical microfluidic manipulation. This is the first demonstration of a UV direct write surface acoustic wave transducer reported to date, made possible only due to the unique qualities of the MER domain engineering process.
Sulla legittimazione attiva in ragione della natura giuridica previdenziale, non retributiva, dei versamenti dovuti alle forme pensionistiche complementari (2018)

Il dato normativo posto dall’art. 8, D.Lgs. n. 252/2005 nel regolamentare il finanziamento alla previdenza complementare e, rispettivamente, i relativi modi attraverso il versamento di contributi a ca­rico del datore di lavoro e del lavoratore, ovvero con il conferimento del TFR maturando, in ragione della natura giuridica previdenziale non retributiva dei versamenti dovuti alle forme pensionistiche complementari, esclude che il relativo credito possa godere del privilegio di cui all’art. 2751-bis, n. 1, c.c. e, per l’effetto, in assenza del nesso di correspettivita tra contribuzione e prestazione lavorati­va, esclude la legittimazione attiva del lavoratore a pretendere il pagamento in suo favore dei contributi o del TFR maturando non versati.

La diversa conclusione comporterebbe, difatti, che in caso di utile riparto si avrebbe l’apprensione definitiva della somma da parte del lavoratore, con l’ulteriore conseguenza di ottenere un risultato ulteriore, rispetto a quello previsto dalla legge, che non consente la monetizzazione, sicche, non essendo possibile realizzare il litisconsorzio nella verifica dello stato passivo, deve ritenersi esclusa la possibilita di emettere una pronuncia di ammissione del credito su richiesta di un soggetto in favore di un terzo, rimasto inerte, attesa la possibilita per il lavoratore di agire per il risarcimento del danno conseguito in ragione della lesione all’aspettativa della prestazione previdenziale individuale