gebhart/patrepeval huggingface dataset:
Dissociation of CO<sub>2</sub> in a low current gliding arc plasmatron (2011)

The process of CO 2 dissociation was studied in a non-equilibrium gliding arc plasmatron (GAP). The GAP was designed not only for efficient reforming but also to ensure significant variability of reactor parameters. The effect of vortex flow configuration on efficiency was also studied in the reactor by comparing forward vortex flow and reverse vortex flow. The maximum thermodynamic efficiency of the dissociation process was determined to be approximately 43%. The high level of efficiency may be attributed to non-equilibrium vibrational excitation of CO 2 and a high-temperature gradient between gliding arc and the surrounding gas that results in fast quenching.
Separation of radiolabelled glycosaminoglycan oligosaccharides by polyacrylamide-gel electrophoresis (1984)

Glycosaminoglycan oligosaccharides generated by treatment of biosynthetically radiolabelled dermatan sulphate and hyaluronic acid with chondroitin AC lyase or testicular hyaluronidase may be resolved into a series of discrete bands by polyacrylamide-gel electrophoresis. Bands were identified by fixation in glacial acetic acid containing 20% (w/v) 2,5-diphenyloxazole followed by fluorography. The bands represented glycans which differed in size by one disaccharide unit. For the larger oligosaccharides (decasaccharides and above) of similar charge: mass ratio, there was a linear relationship between electrophoretic mobility and log Mr. However, the smaller species showed anomalous migration patterns. Consideration of the structures of the fragments produced by the different enzyme treatments suggests that copolymeric and homopolymeric oligosaccharides may be separated by polyacrylamide-gel electrophoresis. There are many potential applications of this technique, foremost amongst them being studies on the molecular size heterogeneity and patterns of enzyme-mediated depolymerization of native glycosaminoglycan chains and investigations into rates of polymer chain elongation and post-polymerization modification reactions so essential to glycosaminoglycan function.
Study of Wild-Type α-Synuclein Binding and Orientation on Gold Nanoparticles (2013)

The disruption of α-synuclein (α-syn) homeostasis in neurons is a potential cause of Parkinson's disease, which is manifested pathologically by the appearance of α-syn aggregates, or Lewy bodies. Treatments for neurological diseases are extremely limited. To study the potential use of gold nanoparticles (Au NPs) to limit α-syn misfolding, the binding and orientation of α-syn on Au NPs were investigated. α-Syn was determined to interact with 20 and 90 nm Au NPs via multilayered adsorption: a strong electrostatic interaction between α-syn and Au NPs in the hard corona and a weaker noncovalent protein-protein interaction in the soft corona. Spectroscopic and light-scattering titrations led to the determinations of binding constants for the Au NP α-syn coronas: for the hard corona on 20 nm Au NPs, the equilibrium association constant was 2.9 ± 1.1 × 10(9) M(-1) (for 360 ± 70 α-syn/NP), and on 90 nm Au NPs, the hard corona association constant was 9.5 ± 0.8 × 10(10) M(-1) (for 5300 ± 700 α-syn/NP). The binding of the soft corona was thermodynamically unfavorable and kinetically driven and was in constant exchange with "free" α-syn in solution. A protease digestion method was used to deduce the α-syn orientation and structure on Au NPs, revealing that α-syn absorbs onto negatively charged Au NPs via its N-terminus while apparently retaining its natively unstructured conformation. These results suggest that Au NPs could be used to sequester and regulate α-syn homeostasis.
Operation Opossum: The raiding party to rescue the Sultan of Ternate, 1945 (2012)

The obscurely named Australian Services Reconnaissance Department (SRD) was asked in February 1945 by the Netherlands Indies Civil Administration (NICA) to conduct an operation to extract the Sultan of Ternate, his family and a group of close supporters from Japanese detention. The operation was developed upon the basis of planning already under way for the rescue of an Australian Spitfire pilot reported to be held in historic Fort Oranje on the east coast of the island of Ternate. He had been shot down south of Ternate, rescued by friendly natives, but a neighbouring pro-Japanese kampong betrayed his presence. After his capture he was incarcerated in the fort and was said to be well treated at first. However, he was later reported by NICA agents to have been tortured and removed from Ternate. However, the operation was not mounted to rescue this pilot.
Repeatability study of mechanomyography in submaximal isometric contractions using coefficient of variation and intraclass correlation coefficient. (1999)

The within-day and between-day repeatability of the mechanomyogram (MMG) was assessed using the coefficient of variation (CV) and the intraclass correlation coefficient (ICC) and was compared with that of the electromyogram (EMG). The MMG and EMG were recorded simultaneously during isometric elbow flexion trials at different submaximal levels of 10% to 90% MVC. The testing session consisting of 9 submaximal trials was repeated 8 times on the same day for estimation of the within-day variation. In order to examine the between-day variation, the same testing session was also performed 8 times over 3 weeks with a 2-day rest interval between each session. The CVs within-day and between-day in both the MMG and EMG did not demonstrate any significant differences relating to the magnitude of force exerted. The CVs combined over all the force levels were approximately 10% within the same day and 25% between days for both the MMG and EMG. These corresponded to the within-day ICC of approximately 0.95 and the between-day ICC of 0.80. The repeatability of the MMG during submaximal isometric contractions of biceps brachii muscles is considered to be similar to that of the more established EMG.
Single‐channel recordings of three types of calcium channels in chick sensory neurones. (1987)

1. T-, and L-type Ca2+ channels were studied in cell-attached patch recordings from the cell bodies of chick dorsal root ganglion neurones. All experiments were performed with isotonic BaCl2 (110 mM) in the recording pipette and with isotonic potassium aspartate in the bathing solution to zero the cell membrane potential. 2. L-type channels are distinguished by a unitary slope conductance of 25 pS, activation over the range of membrane potentials between 0 and +40 mV, little inactivation over the course of a 136 ms depolarization, and availability for opening even at depolarized holding potentials (h.p. greater than -40 mV). L channels show a predominant mode of gating (mode 1) characterized by brief openings (approximately 1 ms), occasionally interspersed with another pattern of gating characterized by much longer openings (mode 2). 3. The dihydropyridine (DHP) Ca2+ agonist Bay K 8644 promotes mode 2 activity and shifts the voltage dependence of L-type channel activation towards more negative potentials. It leaves the unitary current-voltage relation unchanged. 4. Nifedipine, a DHP Ca2+ antagonist, strongly inhibits L-type channel activity through an increase in the proportion of blank sweeps. 5. T-type Ca2+ channels are distinguished by a much smaller unitary slope conductance (8 pS) and by activation and inactivation over relatively negative ranges of potential. Inactivation is complete by the end of 136 ms pulses to test potentials beyond -20 mV. 6. N-type Ca2+ channels are distinguished by an intermediate unitary slope conductance (13 pS), and by activation over a range of potentials between those of T- and L-type channels. Inactivation of N-type channels takes place over an exceptionally broad range of holding potentials (-80 to -20 mV). 7. Cell-attached patch data on the voltage dependence of activation and inactivation of T- and N-type channels are in excellent agreement with results from whole-cell recordings (Fox, Nowycky & Tsien, 1987) if allowances are made for variations in external surface potential. 8. Patches containing one or two channels of a single type were used for analysis of gating kinetics. The predominant pattern of activity for each of the channel types is an exponential distribution of relatively brief (approximately 1 ms) openings, and a bi-exponential distribution of short and long closings. 9. Patches containing all possible combinations of channel types were observed. However, preliminary evidence suggests that channels are distributed unevenly over the cell body; clustering of N-type channels is particularly prominent.(ABSTRACT TRUNCATED AT 400 WORDS)
Synthesis, Temperature Gradient Interaction Chromatography, and Rheology of Entangled Styrene Comb Polymers (2008)

We present the synthesis of polystyrene combs via an improved procedure, which allows the average number of arms to be small (3−5) but well controlled. It is shown that temperature gradient interaction chromatography (TGIC) proves to be a highly effective method for the analysis of these combs, providing directly the distribution of the number of arms on the synthesized comb molecules. We use this arm-number distribution to model the linear rheology of an entangled melt of such combs, via our previously published algorithm [Das et al. J. Rheol. 2006, 50, 207−234], and demonstrate that this compares favorably with the measured linear rheology. A comparison is also made with the predicted rheology for two alternative assumptions about the distribution of arms on the comb, (i) where it is assumed that the addition of arms is an ideal random process and (ii) where there is a fixed number of arms per comb. These predictions also agree well with the experimental results, thus supporting the validity of simpler analytical approaches based on constant arm number, at least for the arm-number distribution considered here.
Cells, embryos and evolution : toward a cellular and developmental understanding of phenotypic variation and evolutionary adaptability (1998)

The Surprising Conservation Of Cellular ProcessesContingencyRegulatory LinkageThe Exploratory Behaviour Of Biological SystemsNoveltyConditionality And CompartmentalizationBody PlansAxis Specification And Reproductive StrategiesDevelopmental Flexibility And RobustnessEvolutionary Diversification Of The Body PlanEvolution And Evolvability
Liquid Metal Droplet and Graphene Co‐Fillers for Electrically Conductive Flexible Composites (2019)

Colloidal liquid metal alloys of gallium, with melting points below room temperature, are potential candidates for creating electrically conductive and flexible composites. However, inclusion of liquid metal micro- and nanodroplets into soft polymeric matrices requires a harsh auxiliary mechanical pressing to rupture the droplets to establish continuous pathways for high electrical conductivity. However, such a destructive strategy reduces the integrity of the composites. Here, this problem is solved by incorporating small loading of nonfunctionalized graphene flakes into the composites. The flakes introduce cavities that are filled with liquid metal after only relatively mild press-rolling (<0.1 MPa) to form electrically conductive continuous pathways within the polymeric matrix, while maintaining the integrity and flexibility of the composites. The composites are characterized to show that even very low graphene loadings (≈0.6 wt%) can achieve high electrical conductivity. The electrical conductance remains nearly constant, with changes less than 0.5%, even under a relatively high applied pressure of >30 kPa. The composites are used for forming flexible electrically-conductive tracks in electronic circuits with a self-healing property. The demonstrated application of co-fillers, together with liquid metal droplets, can be used for establishing electrically-conductive printable-composite tracks for future large-area flexible electronics.
Ion Implantation Damage and Annealing of Silicon as Characterized by Differential Reflectometry (1990)

Ion implantation damage and post‐implantation annealing behavior of silicon (100) wafers have been studied, applying differential reflectometry as the principal investigative tool. Arsenic and silicon ions of various energies and doses were utilized as implantation species. Differential reflectometry is fast and nondestructive and allows an immediate assessment of minute changes in the electronic structure caused by ion implantation or annealing. In addition, the technique allows a measurement of the thickness of an amorphous layer which is formed during high‐dose ion implantation, and an assessment of whether or not an amorphous layer is at the surface or submerged below a crystalline layer. A comparison of our findings with the current understanding of ion implantation damage and with results obtained by cross‐sectional transmission electron microscopy is made. Some kinetic data for isothermal annealing and solid‐phase epitaxial regrowth of amorphous layers are presented.
Limits of implementation: a CD player control case study (2005)

This paper considers the design and implementation of robust multivariable controllers for a compact disc mechanism. The design problem is to achieve good track-following and focusing performance in the presence of disturbances and norm-bounded structured plant uncertainty. This robust performance problem has been solved in the /spl mu/-framework using the DK-iteration scheme. Limits of implementation necessitate the use of sophisticated model reduction techniques and implementation schemes.
Pterostilbene Induces Apoptosis and Cell Cycle Arrest in Human Gastric Carcinoma Cells (2007)

Pterostilbene, an active constituent of blueberries, is known to possess anti-inflammatory activity and also induces apoptosis in various types of cancer cells. Here, the effects of pterostilbene on cell viability in human gastric carcinoma AGS cells were investigated. This study demonstrated that pterostilbene was able to inhibit cell proliferation and induce apoptosis in a concentration- and time-dependent manner. Pterostilbene-induced cell death was characterized with changes in nuclear morphology, DNA fragmentation, and cell morphology. The molecular mechanism of pterostilbene-induced apoptosis was also investigated. The results show the caspase-2, -3, -8, and -9 are all activated by pterostilbene, together with cleavage of the downstream caspase-3 target DNA fragmentation factor (DFF-45) and poly(ADP-riobse) polymerase. Moreover, the results indicate that the Bcl-family of proteins, the mitochondrial pathway, and activation of the caspase cascade are responsible for pterostilbene-induced apoptosis. Pterostilbene markedly enhanced the expression of growth arrest DNA damage-inducible gene 45 and 153 (GADD45 and GADD153) in a time-dependent manner. Flow cytometric analysis indicated that pterostilbene blocked cell cycle progression at G1 phase in a dose- and time-dependent manner. Pterostilbene increased the p53, p21, p27, and p16 proteins and decreased levels of cyclin A, cyclin E, cyclin-dependent kinase 2 (Cdk2), Cdk4, and Cdk6, but the expression of cyclin D1 was not affected. Over a 24 h exposure to pterostilbene, the degree of phosphorylation of Rb was decreased after 6 h. In summary, pterostilbene induced apoptosis in AGS cells through activating the caspase cascade via the mitochondrial and Fas/FasL pathway, GADD expression, and by modifying cell cycle progress and changes in several cycle-regulating proteins. The induction of apoptosis by pterostilbene may provide a pivotal mechanism of the antitumor effects and for treatment of human gastric cancer.
Fragmentation of Homoallylic Alkoxides. Thermolysis of potassium 2‐substituted bicyclo [2.2.2]oct‐5‐en‐2‐alkoxides (1981)

Abstract Thermolysis of the potassium 2‐substituted bicyclo [2.2.2]oct‐5‐en‐2‐alkoxides derived from alcohols 2–17 at 90–120° in hexamethylphosphoric triamide affords unsaturated ketones resulting from allylic bond cleavage. The mechanistic and synthetic aspects of this anionic fragmentation are discussed with reference to the formation of 1‐(3′‐cyclohexenyl)‐2‐alkanones 18–28 via initial heterolytic C(1), C(2)‐bond cleavage in the substrate alkoxide and regioselective, intramolecular protonation of the resultant transient allylic anion.
Epidermal growth factor regulates the in vitro sensitivity of human ovarian carcinoma cells to cisplatin. (1990)

Cisplatin (DDP) is the most effective drug for the treatment of human ovarian cancer, but the mechanisms that determine sen- sitivity to the cytotoxic action of DDP are not well understood. Treatment of two human ovarian carcinoma cell lines with epi- dermal growth factor (EGF) simultaneously increased sensi- tivity to DDP and caused a persistent change in morphology in the absence of any mitogenic effect. Sensitization to DDP was shown to be dependent on both EGF concentration and EGF receptor number in C127 mouse fibroblasts expressing the human EGF receptor after transfection with a pBPV plasmid construct containing the human EGF receptor gene under con- trol of the transferrin receptor 3'-inducible regulator. Sensiti- zation of human ovarian carcinoma cells to DDP was not blocked by inhibition of protein synthesis. EGF did not en- hance sensitivity to DDP or alter morphology in DDP-resis- tant human ovarian carcinoma cells despite the presence of functional EGF receptors on these cells. These results showed that elements of the signal transduction pathway activated by EGF determined cellular sensitivity to DDP, and that a DDP- resistant phenotype is associated with a defect in this signal transduction pathway. (
Large deformation behavior and effective network chain density of swollen poly(N-isopropylacrylamide)–Laponite nanocomposite hydrogels (2011)

Hydrogels were often used in aqueous and/or physiological saline media, thus, the mechanical properties of the swollen gels were of particular importance. Until now, these data were lacking due to the most swollen hydrogels being too weak and brittle to undergo the deformation test at all. The mechanical behavior of swollen poly(N-isopropylacrylamide) (PNIPAm)–Laponite nanocomposite hydrogels (NC gels) were studied with compression and elongation under large strains causing deformation. The swollen NC gels were intact after compression and sustained elongation of up to 500%. Strain hardening was observed in the swollen NC gels for the first time, which was considered to be the extensional limitation of the polymer network chains due to the orientation of the Laponite platelets. Therefore, the strain hardening was enhanced by increasing the Laponite content in the NC gels. When the deformation was low, the compression and elongation stress-deformation curves of the as-prepared and swollen NC gels were described quantitatively with the Mooney–Rivlin model. Whilst for high deformation, Creton's model considering the finite extensibility enabled the prediction of these curves almost quantitatively. Stress-deformation hysteresis was found in the as-prepared and swollen NC gels, which was the result of the deorientation of the clay platelets and relaxation of the polymer chains. The orientation process of the clay platelets dissipated energy during deformation, resulting in a high toughness of the NC gels even in the swollen state. The effective network chain density in the swollen NC gels manifested that the swelling in water only expanded the gel volume and did not damage the cross-linking points. The number of effective network chains attached to one Laponite XLS platelet was almost independent of the clay content, so the addition of clay platelets in the NC gel formed new cross-linking junctions.
Modeling study of activation and propagation delays during stimulation of peripheral nerve fibers with a tripolar cuff electrode (1995)

Computer simulations were performed to investigate the timing of action potential production and propagation in nerve fibers ranging in diameter from 5 to 15 /spl mu/m during stimulation with a tripolar cuff electrode. The influence of stimulus pulse amplitude and duration on size selective excitation and blocking was considered. Because the stimulus duration required to produce anodal blocking depends on the time at which the action potential arrives at the blocking anode, delays in fiber activation and action potential propagation were investigated. They were found to be dependent on fiber diameter as well as stimulus amplitude and duration. The total delay associated with events occurring at the cuff electrode could be expressed as the sum of the activation delay and the propagation delay. Simple exponential equations were proposed for calculating activation and propagation delay as functions of fiber diameter and stimulus amplitude. Estimates of delays in action potential production and propagation may be useful for the design of electrodes and selection of stimuli for producing selective blocking of nerve fibers, and also for the analysis of compound neural signals elicited by electrical stimulation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Increasing the Performance of CDNs Using Replication and Caching: A Hybrid Approach (2005)

Caching and replication have emerged as the two primary techniques for reducing the delay experienced by end users when downloading Web pages. Even though these techniques may benefit from each other, previous research work tends to focus on either one of them separately. In this paper we investigate the potential performance gains by using a CDN server both as a replicator and as a proxy server. We assume a common storage space for both techniques, and develop an analytical model that characterizes caching performance under various system parameters. Based on the models predictions, we can reason whether it is beneficial to reduce the caching space in order to allocate extra replicas. The resulting problem of finding which object replicas should be created where, given that any free space is used for caching, is NP-complete. Therefore, we propose a hybrid heuristic algorithm (based on the greedy paradigm), in order to solve the combined replica placement and storage allocation problem. Our simulation results indicate that a simple LRU caching scheme can considerably improve the response time of HTTP requests, when utilized over a replication-based infrastructure.
Ergothioneine Biosynthetic Methyltransferase EgtD Reveals the Structural Basis of Aromatic Amino Acid Betaine Biosynthesis (2014)

Ergothioneine is an N-α-trimethyl-2-thiohistidine derivative that occurs in human, plant, fungal, and bacterial cells. Biosynthesis of this redox-active betaine starts with trimethylation of the α-amino group of histidine. The three consecutive methyl transfers are catalyzed by the S-adenosylmethionine-dependent methyltransferase EgtD. Three crystal structures of this enzyme in the absence and in the presence of N-α-dimethylhistidine and S-adenosylhomocysteine implicate a preorganized array of hydrophilic interactions as the determinants for substrate specificity and apparent processivity. We identified two active site mutations that change the substrate specificity of EgtD 10(7)-fold and transform the histidine-methyltransferase into a proficient tryptophan-methyltransferase. Finally, a genomic search for EgtD homologues in fungal genomes revealed tyrosine and tryptophan trimethylation activity as a frequent trait in ascomycetous and basidomycetous fungi.