gebhart/patrepeval huggingface dataset:
Structural and pH Dependence of Excited State PCET Reactions Involving Reductive Quenching of the MLCT Excited State of [Ru<sup>II</sup>(bpy)<sub>2</sub>(bpz)]<sup>2+</sup> by Hydroquinones (2011)

The proton-coupled electron transfer (PCET) reaction between the bpz-based photoexcited (3)MLCT state of [Ru(II)(bpy)(2)(bpz)](2+) (bpy = 2,2'-bipyridine, bpz = 2,2'-bipyrazine) and a series of substituted hydroquinones (H(2)Q) has been studied by transient absorption (TA) and time-resolved electron paramagnetic resonance (TREPR) spectroscopy at X-band. When the reaction is carried out in a CH(3)CN/H(2)O mixed solvent system with unsubstituted hydroquinone, the neutral semiquinone radical (4a) and its conjugate base, the semiquinone radical anion (4b), are both observed. Variation of the acid strength in the solvent mixture allows the acid/base dependence of the PCET reaction to be investigated. In solutions with very low acid concentrations, TREPR spectra exclusively derived from radical anion 4b are observed, while at very high acid concentrations, the spectrum is assigned to the protonated structure 4a. At intermediate acid concentrations, either a superposition of spectra is observed (slow exchange between 4a and 4b) or substantial broadening in the TREPR spectrum is observed (fast exchange between 4a and 4b). Variation of substituents on the H(2)Q ring substantially alter this acid/base dependence and provide a means to investigate electronic effects on both the ET and PT components of the PCET process. The TA results suggest a change in mechanism from PCET to direct ET quenching in strongly basic solutions and with electron withdrawing groups on the H(2)Q ring system. Changing the ligand on the Ru complex also alters the acid/base dependence of the TREPR spectra through a series of complex equilibria between protonated and deprotonated hydroquinone radicals and anions. The relative intensities of the signals from radical 4a versus 4b can be rationalized quantitatively in terms of these equilibria and the relevant pK(a) values. An observed equilibrium deuterium isotope effect supports the conclusion that the post-PCET HQ(•)/Q(•-) equilibrium is the most important in determining the 4a/4b ratio at early delay times.
The problem of hot spots in microwave equipment used for preparatory techniques—Theory and practice (1993)

Abstract Electron microscopists who wants to use a microwave (MW) oven to stimulate preparatory processes are sooner or later confronted with the problem of hot spots. It soon becomes clear to the user of any MW oven that the energy distribution—thus the speed of absorbing energy, and hence warming up—varies topographically. The unaware can observe variations in results when the principles of topographic order are not followed meticulously. To understand the hot‐spot phenomenon a certain theoretical knowledge is needed, as presented in this paper. In the 10 years that we have used MW ovens for our preparatory techniques we have learned how to solve the problem of hot spots. Thermographic paint can be applied to record energy distribution. In our studies, we have used a fiberoptic thermometer to follow precisely in time the temperature in the MW‐exposed media, and these observations have provided us with the needed insight to obtain reproducible results. We argue that only when temperature curves are given by the authors can their recipes be used successfully in other laboratories.
Axon Extension Occurs Independently of Centrosomal Microtubule Nucleation (2010)

Centrosome-Free Axonal Regeneration Neuronal axon growth is thought to depend on microtubules that are assembled at the centrosome, the classical microtubule organizing center (MTOC), which may even dictate axon growth. However, such a local trigger of neuronal polarization and focal microtubule nucleation in the cell body appears difficult to reconcile with the sophisticated microtubule arrays observed in neurons. Now, Stiess et al. (p. 704 , published online 7 January) provide evidence, through physical ablation of the centrosome in mammalian neurons, that axon growth is regulated by acentrosomal microtubule nucleation. The findings suggest that the centrosome loses its function as an MTOC during neuronal development, that axon growth depends on decentralized microtubule assembly, and that neuronal differentiation takes place in the absence of a functional centrosome.
Improving multicasting approach in UMTS network (2014)

In several new applications of modern wireless networks like weather forecasting, traffic reports, mobile TV, video on demand, etc., same multimedia contents should be delivered to many users located in different geographical areas. The unicast technology is highly inefficient for such applications thus multimedia broadcast/multicast service (MBMS) was defined by third generation partnership project (3GPP) in 2005. Since then various improvements have been incorporated in the later releases by 3GPP, but there still exists a scope of further improvement in it. The present paper proposes algorithms to improve the multimedia multicasting so that the user can easily obtain the type of service it wants and the burden on network get reduced drastically. The MDV approach is implemented and compared in OPNET Modeler 14.5 with other existing approaches like Standard, Single, and Multiple Multimedia Multicasting approach and yielded better results as compared to these approaches.
Development Of Super High Density Packed Image Guide (1989)

The development of high density ultra-thin image guide is described. For this development a quantitative evaluation system and actual scope evaluation system were adopted. 2000, 3000 and 6000 pixels ultra thin image guides were introduced.
A Simple MAX-CUT Algorithm for Planar Graphs. (2009)

The max-cut problem asks for partitioning the nodes V of a graph G=(V,E) into two sets (one of which might be empty), such that the sum of weights of edges joining nodes in different partitions is maximum. Whereas for general instances the max-cut problem is NP-hard, it is polynomially solvable for certain classes of graphs. For planar graphs, there exist several polynomial-time methods determining maximum cuts for arbitrary choice of edge weights. Typically, the problem is solved by computing a minimum-weight perfect matching in some associated graph. In this work, we present a new and simple algorithm for determining maximum cuts for arbitrary weighted planar graphs. Its running time can be bounded by O(|V|^(1.5)log|V|), similar to the fastest known methods. However, our transformation yields a much smaller associated graph than that of the known methods. Furthermore, it can be computed fast. As the practical running time strongly depends on the size of the associated graph, it can be expected that our algorithm is considerably faster than the methods known in the literature. More specifically, our program can determine maximum cuts in huge realistic and random planar graphs with up to 10^6 nodes.
One‐Pot, Three‐Component Synthesis of 1,4,5‐Trisubstituted 1,2,3‐Triazoles Starting from Primary Alcohols (2012)

Abstract A novel, one‐pot, three‐component approach for the synthesis of 1,4,5‐trisubstituted 1,2,3‐triazoles through the cycloaddition of a wide range of primary alcohols with sodium azide and active methylene ketones in the presence of N ‐( p ‐toluenesulfonyl)imidazole, tetrabutylammonium iodide, and triethylamine in DMF/DMSO has been developed.
Demonstration of high-speed data transmission using MIMO-OFDM visible light communications (2010)

This letter reports an experimental demonstration of high-speed indoor optical wireless Optical multiple-input multiple-output (MIMO)-orthogonal frequency division multiplexing (OFDM) system with an imaging receiver. The system consists of a 2x1 array of white LEDs that transmit data to a 9 channel imaging receiver that uses a 3x3 photodetector array. A total transmission rate of 220Mbit/s at a BER of 10-3 is achieved over a range of 1m. An overview of the design specifications, optical design and experimental setup are reported in this letter, together with results and discussion of how improvements to the system may be achieved. © 2010 IEEE.
Cell surface membrane protein changes during the differentiation of cultured human promyelocytic leukemia HL-60 cells. (1983)

The human promyelocytic leukemia cell line HL-60 was induced to differentiate in vitro by treatment with dimethyl sulfoxide or retinoic acid. Morphological maturation was accompanied by a total loss of transferrin binding and a 7-fold increase in the percentage of cells reducing nitro blue tetrazolium. Cell surface membrane proteins and glycoproteins were labeled with 125I by the lactoperoxidase-H2O2 or 1,3,4,6-tetrachloro-3 alpha, 6 alpha-diphenylglycoluril (Iodo-Gen) methods and analyzed by two-dimensional isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. A minimum of 12 cell surface proteins were unchanged, 3 proteins (Mr 95,000, 87,000, and 77,000) were lost, and up to 7 new proteins (Mr 270,000, 240,000, 150,000, 135,000, 58,000, 56,000, and 50,000) appeared during HL-60 cell differentiation. The kinetics of disappearance of one major labeled cell surface protein (Mr 95,000) within two days during treatment with retinoic acid correlated with the loss of cellular transferrin binding. This protein was identified as the transferrin receptor by affinity absorption of extracts of 125I-surface protein-labeled cells to transferrin-Sepharose beads. The affinity-purified component had molecular weights of 190,000 and 95,000 under nonreducing and reducing conditions, respectively, confirming its dimeric structure. Two-dimensional electrophoresis of cell surface membrane-labeled proteins of normal human granulocytes confirmed the absence of the transferrin receptor and identified cell surface proteins with molecular weight and pI values corresponding to three of the new cell surface proteins which appeared during HL-60 maturation. The most intensely labeled of these had a molecular weight of about 55,000, and was confirmed as being identical to the corresponding Mr 58,000 HL-60 cell surface membrane protein by one-dimensional peptide-mapping analysis. This prominent new Mr 55,000 to 58,000 protein increased continuously throughout retinoic acid-induced maturation and was identified as a major terminal myeloid differentiation cell surface membrane protein.
Feedback inhibition of Akt signaling limits the growth of tumors lacking <i>Tsc2</i> (2005)

The PTEN and TSC2 tumor suppressors inhibit mammalian target of rapamycin (mTOR) signaling and are defective in distinct hamartoma syndromes. Using mouse genetics, we find that Pten and Tsc2 act synergistically to suppress the severity of a subset of tumors specific to loss of each of these genes. Interestingly, we find that the slow-growing tumors specific to Tsc2 +/- mice exhibit defects in signaling downstream of Akt. However, Pten haploinsufficiency restores Akt signaling in these tumors and dramatically enhances their severity. This study demonstrates that attenuation of the PI3K-Akt pathway in tumors lacking TSC2 contributes to their benign nature.
Establishment of Kinetic Zone Diagrams via Simulated Linear Sweep Voltammograms for Soluble-Insoluble Systems (2020)

Due to the need for a rigorous mathematical model that can help to estimate kinetic properties for soluble-insoluble systems, through voltammetric experiments, a Nicholson Semi Analytical Approach was used in this work for modeling and prediction of theoretical linear sweep voltammetry responses for reversible, quasi reversible or irreversible electron transfer reactions. The redox system of interest is a one-step metal electrodeposition process. A rigorous analysis of simulated linear scan voltammetric responses following variation of dimensionless factors, the rate constant and charge transfer coefficients in a broad range was studied and presented in the form of the so called kinetic zones diagrams. These kinetic diagrams were divided into three kinetics zones. Interpreting these zones leads to empirical mathematical models which can allow the experimenter to determine electrodeposition reactions kinetics whatever the degree of reversibility. The validity of the obtained results was tested and an excellent experiment–theory agreement has been showed.
Evaluation in cats of a new material for cranioplasty: a composite of plaster of Paris and hydroxylapatite (1988)

The materials ordinarily used to reconstruct bone defects in the calvaria and facial bones either are difficult to shape, are partially resorbed by the body, or are likely to become infected if used near a contaminated area such as the frontal sinus. Calcium sulfate hemihydrate (plaster of Paris) has been known for years to have excellent reparative qualities in bone defects, but ordinarily it is quickly resorbed. Consequently, a new material, a composite of a dense form of plaster of Paris and hydroxylapatite, was devised to provide nonabsorbable hydroxylapatite particles for bone to form around and within during the phase of plaster absorption. Two types of this material were evaluated in cranial defects in cats. Each of the plaster of Paris/hydroxylapatite mixtures was placed into a surgically unroofed frontal sinus and into a contralateral parietal trephine hole in a group of 32 cats. Two cats in each group succumbed to anesthesia, leaving two sets of 30 cats. During the entire follow-up period there was only one other death, with no evidence of wound infection, wound dehiscence, implant rejection, or cerebral dysfunction among the survivors. The cats in each group were sacrificed at 1, 2, 3, 5, 7, 8, 9, 10, or 12 months after operation. Following sacrifice, both the frontal and parietal defects were exposed and examined visually, histologically, and with histomorphometric analysis for new bone formation. New bone formation was present as early as 1 month after operation and continued to increase during the 12 months of the study. Based upon these osteogenic qualities, the ease of shaping the composite, and the lack of infection in the frontal sinus region, it is concluded that this substance could be a valuable new material for human cranioplasty.
GeoIP clustering: Solving replica server placement problem in content delivery networks by clustering users according to their physical locations (2013)

Content delivery networks have emerged to conquer massive requests problem in popular web services. One of the major issues in CDNs is the replica server placement problem. If the replica servers are geographically closer to the users, overall bandwidth consumption and the users' perceived latency will be reduced significantly. In this paper we have used IP geolocation services to achieve the users' locations in terms of latitude and longitude. Then we have clustered users according to their coordinates. Locating servers around the cluster centers, provides better performance of CDN.
A two-channel recording VCR using orthogonal arrangement of heads (1989)

The authors describe a novel design technique for FM carrier allocation and an improved two-channel recording technique allowing both standard and long-play modes. Consequently, the experimental VCR can be used as a wide-screen-TV recorder. Experimental results confirm that this high-efficiency recording technique provides a picture quality nearly equal to that of the VCR for broadcast use with 1/2-inch conventional video tape. For users of conventional TV a converter from wide-screen to conventional signal format has been developed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Least-squares migration of multisource data with a deblurring filter (2011)

ABSTRACT Least-squares migration (LSM) has been shown to be able to produce high-quality migration images, but its computational cost is considered to be too high for practical imaging. We have developed a multisource least-squares migration algorithm (MLSM) to increase the computational efficiency by using the blended sources processing technique. To expedite convergence, a multisource deblurring filter is used as a preconditioner to reduce the data residual. This MLSM algorithm is applicable with Kirchhoff migration, wave-equation migration, or reverse time migration, and the gain in computational efficiency depends on the choice of migration method. Numerical results with Kirchhoff LSM on the 2D SEG/EAGE salt model show that an accurate image is obtained by migrating a supergather of 320 phase-encoded shots. When the encoding functions are the same for every iteration, the input/output cost of MLSM is reduced by 320 times. Empirical results show that the crosstalk noise introduced by blended sources is more effectively reduced when the encoding functions are changed at every iteration. The analysis of signal-to-noise ratio (S/N) suggests that not too many iterations are needed to enhance the S/N to an acceptable level. Therefore, when implemented with wave-equation migration or reverse time migration methods, the MLSM algorithm can be more efficient than the conventional migration method.
Ferroelectric Behavior in the Copolymer of Vinylidenefluoride and Trifluoroethylene (1980)

The linear and nonlinear dielectrical and depolarization processes of the copolymer of vinylidene fluoride and trifluoroethylene have been measured. The D vs. E hysteresis loop below room temperature indicates the ferroelectricity of this copolymer. The dielectric anomaly and the disappearance of remnant polarization at T0=70°C suggest that T0 is the phase transition temperature from the ferroelectricity to the paraelectricity phase. Results are analyzed on the basis of Weiss-type semimolecular theory.
Context-aware notification for wearable computing (2004)

In this paper we propose to use context information obtainedfrom body-worn sensors to mediate notifications fora wearable computer. In particular we introduce a modelwhich uses two axes, namely personal and social interruptabilityof the user in order to decide both whether or notto notify the user and to decide which notification modalityto use. Rather than to model and recognize the completecontext of the user we argue that personal and social interruptabilitycan be derived directly from various sensors bythe combination of tendencies. First experimental resultsshow the feasibility of the approach using acceleration, audio,and location sensors.
Metal-Free Electrically Conductive Bioinspired Adhesive Polymers (2019)

The traditional electrically conductive adhesives (ECAs) include heterogeneous metallic and/or carbon-based fillers blended with the organic adhesive polymer matrix. However, those heterogeneous-blended ECAs have serious challenges with aggregation, weight, synthetic complexity, large filler contents, and price. This work reports a metal-free, high-performance, and electrically conductive fully organic polymer adhesive, poly(N-methacryloyl-3,4-dihydroxyl-l-phenylalanine-co-3-sulfopropyl methacrylate):poly(3,4-ethylenedioxythiophene) (PMS:PEDOT), that is excellently dispersible in water, easy-to-use, lightweight, highly flexible, and biocompatible and has a low-process temperature (23 °C). The new ECA, PMS:PEDOT is prepared in two steps. First, a flexible linker containing copolymer, which possesses the bioinspired adhesive moiety catechol and sulfonate, is synthesized by radical polymerization. Second, EDOT is oxidatively polymerized in the presence of the flexible copolymer matrix to prepare the new ECA (PMS:PEDOT). The PMS:PEDOT exhibits high electrical conductivity up to 2.5 S/cm after annealing and glycerol addition. The bulk adhesion test (lap shear strength tests) showed 1.62 MPa which is much higher than various other commercial adhesives such as epoxy, glass bonder, and ethylene vinyl acetate-based hot melt. This newly developed ECA successfully demonstrates an efficient electrical connection on a circuit board and PET film. This work introduces a new class of materials, a fully organic conducting polymer adhesive, which will become essential for fast growing applications including conducting ink, bioelectronics, batteries, photovoltaics, and ultrathin microsized electronic devices.
Membrane separation processes for clean production (1998)

Abstract Clean production can be considered as a strategic element in manufacturing technology for present and future products in the chemical industry. Demand is focussed on the development of cost‐effective technologies, the optimization of processes including separation steps, alternative processes for the reduction of waste, optimization of the use of resource and improvements in production efficiency. In many cases an environmentally friendly alternative to conventional separation processes could be membrane separation. Membrane separation techniques are suitable for mixtures of liquids, gases and vapors. Some examples of successful applications in the areas of waste water treatment and vapor recovery are given. Demands, advantages and problems of separation with membranes are also discussed.
Use of a superconductive gradiometer in an ultrasensitive electromagnetic metal detector (1989)

The authors present an electromagnetic gradiometer that uses a SQUID (superconductor quantum interference device) sensor as the receiver in an active, electromagnetic detector of nonferrous as well as ferrous objects. The gradiometer pickup loops sit in the center of magnetic coils that generate a time-varying magnetic field inducing eddy currents in conductive bodies. The gradiometer measures the secondary magnetic field of the eddy currents. The SQUID's sensitivity at frequencies below 1 kHz makes electromagnetic metal detectors practical in the marine environment, where the electrical conductivity of seawater precludes the use of conventional systems. The authors describe a prototype system that attains a detection range of 10 m in seawater for targets 50 cm in diameter. It operates at frequencies from 1 Hz to a few hundred Hz. Uses of the electromagnetic gradiometer include locating naval mines buried in sea bottom sediments and hunting undersea treasure. The system's response to the seawater itself enables application to airborne electromagnetic bathymetry. Over land, its sensitivity to crustal conductivity contrasts makes it suitable for airborne mineral exploration.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Diversity in the Properties of Two Sialidase Isoenzymes Produced by<i>Clostridium perfringens</i>spp. (1995)

Clostridium perfringens produces two sialidases, one of which has a molecular mass of 71 kDa and is secreted, while the 'small', 43 kDa isoenzyme remains in the cells. The secreted, higher molecular mass sialidases of two different clostridial strains, DSM756T and A99, exhibit maximum activity at pH 5.5 and at 51 or 55 degrees C, respectively. The molecular mass of both enzymes is 71 kDa in SDS-PAGE and 63 kDa as determined by gel-filtration, which indicates the absence of subunits. Natural sialidase substrates are hydrolyzed at comparably high rates, e.g. the glycoproteins fetuin and bovine submandibular gland mucin, the homopolymer colominic acid, and the ganglioside mixture from bovine brain. The partially purified 'small' isoenzyme from C. perfringens A99 cells had similar properties to the corresponding recombinant sialidase isolated from the Escherichia coli host. It is located inside the clostridial and E. coli cells and exhibits maximum activity at pH 6.1 and 37 degrees C. A relative molecular mass of 32,000 was found with FPLC gel-filtration chromatography, while primary structure analysis yielded a value of 43,000. It differs a significantly from the 'large' isoenzyme by substrate specificity. Preferred substrates are oligosaccharides, while other, more complex sialoglycoconjugates are hydrolyzed only at very low rates. alpha 2,3-linkages are hydrolyzed much faster than alpha 2,6-bonds.