gebhart/patrepeval huggingface dataset:
Dissecting the roles of VP0 cleavage and RNA packaging in picornavirus capsid stabilization: the structure of empty capsids of foot-and-mouth disease virus (1997)

Empty capsids of foot-and-mouth disease virus (FMDV) type A22 Iraq 24/64, whose structure has been solved by X-ray crystallography, are unusual for picornaviruses since they contain VP2 and VP4, the cleavage products of the protein precursor VP0. Both the N terminus of VP1 and the C terminus of VP4, which pack together close to the icosahedral threefold symmetry axis where three pentamers associate, are more disordered in the empty capsid than they are in the RNA-containing virus. The ordering of these termini in the presence of RNA strengthens interactions within a single protomer and between protomers belonging to different pentamers. The disorder in the FMDV empty capsid forms a subset of that seen in the poliovirus empty capsid, which has VP0 intact. Thus, VP0 cleavage confers stability on the picornavirus capsid over and above that attributable to RNA encapsidation. In both FMDV and poliovirus empty capsids, the internal disordering uncovers a conserved histidine which has been proposed to be involved in the cleavage of VP0. A comparison of the putative active sites in FMDV and poliovirus suggests a structural explanation for the sequence specificity of the cleavage reaction.
Digitized Heat Transfer: A New Paradigm for Thermal Management of Compact Micro Systems (2008)

This paper presents theoretical and numerical results describing digitized heat transfer (DHT), a newly developing active thermal management technique for high-power density electronics and integrated micro systems. In describing DHT, we numerically investigate the mass, momentum, and energy equations governing the flow within a translating microdroplet. Our analysis shows the existence of a pair of recirculation zones inside the droplet. This internal circulation within discrete fluid slugs results in significantly increased overall heat transfer coefficients when compared to continuous Graetz-type flows. The internal circulation drives the cold fluid in the middle of the droplet to the vicinity of the walls and creates a higher local temperature difference between the wall and the fluid in contact with the wall, resulting in higher heat transfer rates. Nusselt numbers characterizing DHT flow are also shown to exhibit periodic fluctuations with a period equal to the characteristic time scale for droplet circulation. The overall effect of discretizing a flow on heat transfer capability is described and characterized in terms of a nondimensional circulation number defined by the ratio of characteristic thermal diffusion and fluid circulation time scales. DHT coolants, including liquid metals and alloys, are proposed, and their physical properties are shown to enable handling of significantly higher heat transfer rates than classical air- or water-cooled methods. The actuation method for DHT coolant transport is also outlined, and shown to provide the capability for active, on-demand suppression of transient hot spots. This overall analysis defines the key parameters for optimization of the DHT method and forms the basis of ongoing experimental work.
Contributors (2008)

This DOI is not currently attached to any metadata records. DOIs can’t actually ever be deleted (they’re persistent), but sometimes our members create DOIs in error. We do have a process to approximate deletion which we follow only in rare cases where the DOI has been genuinely created in error, and most crucially, if the DOI has never been published anywhere online or in print and never otherwise distributed to or communicated with anyone (authors, readers, reviewers, etc.
Ultraschall zur Bestimmung der Kristallwachstumskinetik (2003)

Abstract No abstracts.
Reversibly Switching Bilayer Permeability and Release Modules of Photochromic Polymersomes Stabilized by Cooperative Noncovalent Interactions (2015)

We report on the fabrication of photochromic polymersomes exhibiting photoswitchable and reversible bilayer permeability from newly designed poly(ethylene oxide)-b-PSPA (PEO-b-PSPA) diblock copolymers, where SPA is spiropyran (SP)-based monomer containing a unique carbamate linkage. Upon self-assembling into polymersomes, SP moieties within vesicle bilayers undergo reversible phototriggered isomerization between hydrophobic spiropyran (SP, λ2 > 450 nm irradiation) and zwitterionic merocyanine (MC, λ1 < 420 nm irradiation) states. For both SP and MC polymersomes, their microstructures are stabilized by multiple cooperative noncovalent interactions including hydrophobic, hydrogen bonding, π-π stacking, and paired electrostatic (zwitterionic) interactions, with the latter two types being exclusive for MC polymersomes. Control experiments using analogous block copolymers of hydrophobic SP monomer with a carbonate linkage (SPO) and conventional spiropyran methacrylate monomer (SPMA) containing a single ester functionality were then conducted, revealing that carbamate-incurred hydrogen bonding interactions in PEO-b-PSPA are crucial for polymersome stabilization in the zwitterionic MC state. Moreover, reversible phototriggered SP-to-MC polymersome transition is accompanied by membrane polarity and permeability switching from being nonimpermeable to selectively permeable toward noncharged, charged, and zwitterionic small molecule species below critical molar masses. Intriguingly, UV-actuated MC polymersomes possess two types of release modules: (1) sustained release upon short UV irradiation duration by taking advantage of the unexpectedly slow spontaneous MC-to-SP transition kinetics (t1/2 > 20 h) under dark conditions; (2) on-demand and switchable release under alternated UV-vis light irradiation. We further demonstrate photoswitchable spatiotemporal release of 4',6-diamidino-2-phenylindole (DAPI, cell nuclei-staining dye) within living HeLa cells.
Electrical-Thermal Coupled Finite Element Model of High Temperature Superconductor for Resistive Type Fault Current Limiter (2011)

A multi-physics finite element model of high temperature superconductors (HTS) is presented in this article. An electrical model based on a set of Maxwell's equations and E-J power law is used to solve the critical state of the superconductor. A heat transfer model is added to the electrical model to calculate the temperature distribution and therefore investigate the J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> (T) dependence of the superconductor. The model is used to study the quench behavior of YBCO-coated conductors for the application of resistive type fault current limiters. Some numerical techniques are applied and assumptions are made to simplify the calculation and improve convergence. An equivalent heat transfer coefficient which is much larger than the normal heat transfer coefficient is applied to the region surrounding the superconductors. This equivalent coefficient represents the drastic heat exchange during the boiling of the liquid nitrogen. The cross-section of YBCO tapes is divided into several sub-domains. The temperature is assumed to be uniform in each sub-domain. This simplification significantly improves the convergence of model and still is able to keep a reasonable level of accuracy. The model is then able to simulate the whole process of YBCO tapes quenching and recovering to superconducting state. The numerical results are compared with the fault current experiments and excellent agreement is obtained.
Improved production of deglucosylated platycodin D from saponins from balloon flower leaf by a food-grade enzyme using high hydrostatic pressure (2021)

Platycosides, saponins contained in balloon flower, which have been used as food health supplements for respiratory diseases, have diverse pharmacological effects. Platycosides exhibit better pharmacological activity by hydrolyzing their own sugars. However, to date, there have been no studies on the production of deglucosylated platycodin D suitable for food applications. In this study, Pluszyme 2000P, which was derived from <i>Aspergillus niger</i>, a food-grade microorganism, was used to completely convert platycoside E into deglucosylated platycodin D. For an efficient and economical production of deglucosylated platycodin D, the productivity was improved approximately 2.4 times by application of high hydrostatic pressure and the discarded balloon flower leaf was used as a substrate. As a result, deglucosylated platycodin D was produced with the highest concentration (3.49 mg/mL) and productivity (581.7 mg/L/h) reported so far. Our results contribute to functional saponin production and the related food industries.
Upconversion pumped thulium-doped fluoride fiber amplifier and laser operating at 1.47 μm (1995)

A 1.064-/spl mu/m band upconversion pumped Tm/sup 3+/-doped fluoride fiber amplifier and a laser both operating at 1.47 /spl mu/m are investigated in detail. The two devices are based on the /sup 3/F/sub 4//spl rarr//sup 3/H/sub 4/ transition in a trivalent thulium ion, which is a self-terminating system. When pumped at 1.064 /spl mu/m, the amplifier has a gain of over 10 dB from 1.44 to 1.51 /spl mu/m and a low-noise characteristic. Also, the fiber laser generates a high-output power of over 100 mW with a slope efficiency of 59% at around 1.47 /spl mu/m. These levels of performance will be important for optical communication systems. >
Synovial biology and T cells in rheumatoid arthritis (2005)

Events that occur in rheumatoid arthritis synovial tissues are responsible for the signs and symptoms of joint inflammation and for the eventual destruction of articular and periarticular structures that lead to joint dysfunction and disability. The three most abundant cell populations in RA synovium are synovial macrophages (type A synoviocytes), synovial fibroblasts (type B synoviocytes) and infiltrating T lymphocytes. Other important cell populations include B lymphocytes, dendritic cells, plasma cells, mast cells and osteoclasts. Our current understanding of rheumatoid arthritis is moving beyond previous concepts that view this disease as the consequence of a specific and focused humoral or cellular autoimmune response to a single autoantigen. Rather, a new view of rheumatoid arthritis is emerging, which seeks to understand this disease as the product of pathologic cell-cell interactions occurring within a unique and defined environment, the synovium. T lymphocytes in rheumatoid arthritis synovium interact closely with dendritic cells, the most potent antigen-presenting cell population in the immune system. T cells also interact with monocytes and macrophages and cytokine-activated T cells may be, especially, suited to trigger production of the important cytokine TNFalpha by synovial macrophages. Recent evidence also suggests a potent bidirectional interaction between synovial T cells and synovial fibroblasts, which can lead to activation of both cell types. An important role for synovial B lymphocytes has been emphasized recently, both by experimental data and by results of clinical interventions. B cells in synovium can interact with fibroblasts as well as with other cells of the immune system and their potential role as antigen-presenting cells in the joint is as yet underexplored. Rheumatoid arthritis synovium may be one of the most striking examples of pathologic, organ-specific interactions between immune system cells and resident tissue cell populations. This view of rheumatoid arthritis also leads to the prediction that novel approaches to treatment will more logically target the intercellular communication systems that maintain such interactions, rather than attempt to ablate a single cell population.
Microwave Characterization of a Wafer-Level Packaging Approach for RF MEMS Devices Using Glass Frit Bonding (2014)

This paper presents the microwave characterization of a wafer level packaging approach for RF MEMS devices, using glass frit as the bonding material. Coplanar waveguide transmission lines are packaged by silicon caps to carry out the RF characterization of the package structure. Prior to bonding of the cap on the transmission lines, cap wafers are bulk micromachined to form the cavities for housing the device to be packaged and pad windows to access the RF ports of the devices. Lateral feedthroughs are designed under the glass frit ring transitions in order to decrease the impedance loading effect of the silicon cap and the glass frit ring. The package is implemented using both high and low resistive silicon wafers in order to assess the microwave effects of cap wafer. A circuit model is used to extract the parameters of the feedthrough from the RF measurements. The loss of the feedthrough is measured to be 0.1 dB/transition at 10 GHz for high resistive silicon caps demonstrating the viability of glass frit in the packaging of RF MEMS devices.
Experimental Study on the Influence of Dot Geometry on Ink Transfer in Gravure Printing (2011)

The pattern shape engraved on the gravure printing roll is one of the most important factors influencing ink transfer. This study focuses on the relations between dot geometry engraved on gravure printing roll and the ink transfer during the gravure printing process. The influence of dot width on printed patterns will be demonstrated. Results reveal that as the width of a dot on the printing roll increases, the ink transfer rate also increases. But over a certain size of width, surface uniformity began to recede. Therefore, proper dot geometry on the printing roll should be decided to guarantee good printing quality according to printing conditions and expected performance of the electronic devices.
Fast iterative segmentation of high resolution medical images (2002)

Various applications in positron emission tomography (PET), single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) require segmentation of 20 to 60 high resolution images of size 256/spl times/256 pixels in 3-9 seconds per image. This places particular constraints on the design of image segmentation algorithms. This paper examines the trade-offs in segmenting images based on fitting a density function to the pixel intensities using curve-fitting versus the maximum likelihood method. A quantized data representation is proposed and the EM algorithm for fitting a finite mixture density function to the quantized representation for an image is derived. A Monte Carlo evaluation of mean estimation error and classification error showed that the resulting quantized EM algorithm dramatically reduces the required computation time without loss of accuracy.
Cell division drives DNA methylation loss in late-replicating domains in primary human cells (2022)

DNA methylation undergoes dramatic age-related changes, first described more than four decades ago. Loss of DNA methylation within partially methylated domains (PMDs), late-replicating regions of the genome attached to the nuclear lamina, advances with age in normal tissues, and is further exacerbated in cancer. We present here experimental evidence that this DNA hypomethylation is directly driven by proliferation-associated DNA replication. Within PMDs, loss of DNA methylation at low-density CpGs in A:T-rich immediate context (PMD solo-WCGWs) tracks cumulative population doublings in primary cell culture. Cell cycle deceleration results in a proportional decrease in the rate of DNA hypomethylation. Blocking DNA replication via Mitomycin C treatment halts methylation loss. Loss of methylation continues unabated after TERT immortalization until finally reaching a severely hypomethylated equilibrium. Ambient oxygen culture conditions increases the rate of methylation loss compared to low-oxygen conditions, suggesting that some methylation loss may occur during unscheduled, oxidative damage repair-associated DNA synthesis. Finally, we present and validate a model to estimate the relative cumulative replicative histories of human cells, which we call "RepliTali" (Replication Times Accumulated in Lifetime).
Multibody Dynamic Characteristics of Wingtip-jointed Composite Aircrafts (2019)

Multibody dynamic modeling and characteristics in the Wingtip-jointed process of a new-concept composite aircraft system is investigated. The Wingtip-jointed aircrafts are regarded as variable geometry multiple rigid bodies, and the seven-degree-of-freedom nonlinear dynamic model is established by mathematical derivation. Numerical modeling methods and specific multibody dynamic balance strategies of Wingtip-jointed aircrafts are included. Furthermore, utilizing the Jacobian linearization approach, the nonlinear dynamics equations of multibody system are linearized for the computation of multibody system modes. The corresponding result indicates that the longitudinal and lateral movements are highly coupled, and an obviously diverging mode is investigated in the incoming seventh degree of freedom. In that the safety and stability of the composite flight process of two aircrafts with wingtips coupled should be guaranteed, the necessity of a control strategy design is concluded. The research conclusion can be as great reference for new-concept composite aircrafts model establishment and multibody dynamic characteristic investigation.
ChemInform Abstract: Palladium‐Catalyzed Hydrogenolysis of Allylic Compounds with Formic Acid: Its Application to Organic Synthesis (1992)

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.
A new method for preparing D-penicillamine. Reaction of benzylpenicilloic acid .ALPHA.-amides with arylamines. (1988)

Benzylpenicilloic acid α-amides (1a-d) prepared by aminolysis of benzylpenicillin were treated with arylamines (2, 7, 9 and 13a-f) in the presence of acetic acid to give D-penicillamine (3) in good yield and high purity. The structures pf the by-products formed in these reactions were also determined.
Best efficiency point management of an underwater compressed air energy storage system using PMSM drive (2017)

This paper deals with an underwater compressed air energy storage system. The power conversion chain is composed of a PWM-VSI-PMSM driving an underwater compression system. The excess energy is stored in form of compressed air in a tank located on the seabed. A multi-physic dynamical model of the power conversion chain is established. Considering conversion efficiency performances and system operating constraints, a control strategy management is developed. It consists in constraining the pump operating at the best efficiency point. From these considerations, a predicted speed profile is generated. The mechanical equation is identified as a first order system with a variable time parameter. To ensure the speed tracking, a RST controller is synthetized.
Optimal data fusion in the presence of sensorimotor transformation noise (2010)

In order to integrate cues from different perceptual modalities the cues must be brought into a common coordinate frame. Previous work in cue combination assumes that no sensorimotor transformation noise (STN) is present during multi-modal cue integration. The goal of the present study is to show that the choice of common coordinate frame matters in the presence of STN, both to generate optimal estimates, and in terms of human performance. Theoretically, we demonstrate that performing cue combination in the coordinate frame of the most reliable individual cue is optimal, when STN is present. In addition, we model integration of information across trials as Bayesian learning with forgetting, and show that the learned posterior distributions should also be stored in the most reliable coordinate frame. Given that vision is dominant for many tasks, this provides a possible theoretical explanation for the common empirical finding that object position estimates are stored in eye position coordinates (e.g., Batista, et. al, 1999). These theoretical results will be used to model findings from a reaching task. The task involved reaching to a cylindrical object, whose location was specified by visual and haptic information. STN was varied by changing the relationship between the head, eyes, and object. The results show that reach trajectories systematically vary as a function of STN. Moreover, reaches are consistent with predictions made by storing estimates of the target's location in the most reliable coordinate frame. Overall, the results of this study suggest that coordinate frames are not interchangeable — for a given task there may be a preferred frame of reference.
LDH-TiO2 Composite for Selenocyanate (SeCN−) Photocatalytic Degradation: Characterization, Treatment Efficiency, Reaction Intermediates and Modeling (2022)

Selenium as a nutrient has a narrow margin between safe and toxic limits. Hence, wastewater discharges from selenium-containing sources require appropriate treatment that considers health concerns and stringent selenium-related water treatment standards. This work examined the use of a photocatalysis-cum-adsorption system based on a layered double hydroxide coupled with TiO2 (LDH-TiO2) to remove aqueous phase selenocyanate (SeCN−), which is difficult to treat and requires specific treatment procedures. The synthesized LDH and LDH-TiO2 composite samples were characterized using the X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and thermogravimetry analysis (TGA) methods. The XRD results for the uncalcined LDH indicated a hydrotalcite mass with a rhombohedral structure, whereas increasing the calcination temperature indicated transition to an amorphous state. FESEM results for the LDH-TiO2 matrix indicated round titanium dioxide particles and LDH hexagonal layers. The TGA findings for uncalcined LDH showed a gradual decrease in weight up to 250 °C, followed by a short plateau and then a sharp decrease in LDH weight from 320 °C, with a net weight loss around 47%. Based on the characterization and initial selenocyanate adsorption results, the 250 °C calcined LDH-TiO2 matrix was used for the selenocyanate photocatalysis. A ~100% selenium removal was observed using LDH:TiO2 at a 1.5:1 w/w ratio with a 2 g/L dose, whereas up to 80% selenium removal was noted for LDH:TiO2 at a 0.5:1 w/w ratio. The respective difference in the efficiency of selenium treatment was attributed to enhanced LDH-based adsorption sites in the enhanced LDH:TiO2 w/w ratio. Furthermore, the selenite and selenate that occurred during SeCN− photocatalytic degradation (PCD) were also nearly completely removed via adsorption. An optimization exercise using response surface methodology (RSM) for total selenium removal showed R2 values of more than 0.95, with a prediction accuracy of more than 90%. In summary, the present findings show that the use of a photocatalysis-cum-adsorption system based on LDH-TiO2 is a promising technique to treat industrial wastewater discharges for selenocyanate and also remove the resulting intermediates.