gebhart/patrepeval huggingface dataset:
Negative cooperativity within individual tetramers of Escherichia coli single strand binding protein is responsible for the transition between the (SSB)35 and (SSB)56 DNA binding modes (1988)

We have examined the binding of the oligonucleotide dT (pT)34 to the Escherichia coli SSB protein as a function of NaCl and MgCl2 concentration (25 degrees C, pH 8.1) by monitoring the quenching of the intrinsic protein fluorescence. We find two binding sites for dT(pT)34 per single strand binding (SSB) protein tetramer, with each site possessing widely different affinities depending on the salt concentration. At 200 mM NaCl, we observe nearly stoichiometric binding of dT(pT)34 to both binding sites within the SSB tetramer, although a difference in the affinities is still apparent. However, when the NaCl concentration is lowered, the overall affinity of dT(pT)34 for the second site on the SSB tetramer decreases dramatically. At 1.5 mM NaCl, only a single molecule of dT(pT)34 can bind per SSB tetramer, even with a 10-fold molar excess of dT(pT)34. MgCl2 is effective at 100-fold lower concentrations than NaCl in promoting the binding of the second molecule of dT(pT)34. This binding behavior reflects an intrinsic property of the SSb tetramer, since it is also observed upon binding of smaller oligonucleotides, and the simplest explanation is that a salt-dependent negative cooperativity exists between DNA binding sites within the SSB tetramer. This phenomenon is also responsible for the transition between the two SSB-single strand (ss) polynucleotide binding modes that cover 35 and 56 nucleotides per tetramer [Bujalowski, W., & Lohman, T. M. (1986) Biochemistry 25, 7799-7802]. Extreme negative cooperativity stabilizes the (SSB)35 binding mode, in which the SSB tetramer binds tightly to ss DNA with only two of its subunits while the other two subunits remain unligated.(ABSTRACT TRUNCATED AT 250 WORDS)
Clinical Presentation and Outcome of Patients with HIV Infection and Tuberculosis Caused by Multiple-Drug-resistant Bacilli (1992)

Tuberculosis caused by multiple-drug-resistant bacilli in patients with HIV infection is associated with widely disseminated disease, poor treatment response with an inability to eradicate the organism, and substantial mortality.
Off-Road Drivable Area Extraction Using 3D LiDAR Data (2020)

We propose a method for off-road drivable area extraction using 3D LiDAR data with the goal of autonomous driving application. A specific deep learning framework is designed to deal with the ambiguous area, which is one of the main challenges in the off-road environment. To reduce the considerable demand for human-annotated data for network training, we utilize the information from vast quantities of vehicle paths and auto-generated obstacle labels. Using these autogenerated annotations, the proposed network can be trained using weakly supervised or semi-supervised methods, which can achieve better performance with fewer human annotations. The experiments on our dataset illustrate the reasonability of our framework and the validity of our weakly and semi-supervised methods.
Improved THz imaging with a virtual-source based synthetic aperture focusing technique and coherence weighting (2009)

We combine a virtual-source based synthetic aperture focusing technique with coherence weighting to overcome the limited depth-of-focus of high numerical aperture THz optics. Images show depth-independent spatial resolution and a 14 dB improvement in SNR.
On the dynamics and control of a plasticating extruder (1982)

Abstract In recent years, there have been many papers published on the application of process control to plasticating extruders. Much of the literature concentrates on the more classical control techniques. However, recent research has studied the application of stochastic identification techniques for building transfer function models for the extruder. In particular, the relationship of screw speed to die pressure and temperature has been studied. In the present work, both step tests and pseudorandom binary sequence tests were used to study the process dynamics of a 38 mm Killion extruder having a Iength‐to‐diameter ratio of 24:1. This study concentrates on the regulation of the extruder pressure in the face of its inherent surging characteristics. Variations in the quality of the feed plastic were studied through pulse and step changes in input polymer composition. Significant control problems resulted from measurement noise, which appeared at the same frequency as the screw rotation speed. Various mathematical filters to reduce the effect of this noise on the control variables were studied.
Confinement factor and absorption loss of AlInGaN based laser diodes emitting from ultraviolet to green (2009)

Confinement factor and absorption loss of AlInGaN based multiquantum well laser diodes (LDs) were investigated by numerical simulation based on a two-dimensional waveguide model. The simulation results indicate that an increased ridge height of the waveguide structure can enhance the lateral optical confinement and reduce the threshold current. For 405 nm violet LDs, the effects of p-AlGaN cladding layer composition and thickness on confinement factor and absorption loss were analyzed. The experimental results are in good agreement with the simulation analysis. Compared to violet LD, the confinement factors of 450 nm blue LD and 530 nm green LD were much lower. Using InGaN as waveguide layers that has higher refractive index than GaN will effectively enhance the optical confinement for blue and green LDs. The LDs based on nonpolar substrate allow for thick well layers and will increase the confinement factor several times. Furthermore, the confinement factor is less sensitive to alloys composition of waveguide and cladding layers, being an advantage especially important for ultraviolet and green LDs.
Intramolecular Electronic Energy Transfer in Ruthenium(II) Diimine Donor/Pyrene Acceptor Complexes Linked by a Single C−C Bond (1997)

The photophysical behavior of [(bpy)2Ru(L)]2+ complexes (L = 4-(1''-pyrenyl)-2,2'-bipyridine, bpy-pyr; 2-(1'-pyrenyl)-1,10-phenanthroline, phen-pyr; and 2-(2'-naphthyl)-1,10-phenanthroline, phen-nap) was investigated in solutions and frozen matrices. The conformation of the linked pyrene differs in the two complexes: The pyrene moiety is conformationally constrained to be nearly perpendicular to the phenanthroline in the phen-pyr complex while the pyrene in the bpy-pyr complex has much greater flexibility about the C−C bond linking the ligand and the pyrene. The 3MLCT excited state of the Ru(II) diimine complex and the 3(π → π*) state of the pyrenyl substituent are nearly isoenergetic; the 3MLCT state is the lowest energy state in the bpy-pyr complex, and the pyrene 3(π → π*) state is lower in energy for the phen-pyr complex. The bpy-pyr complex is unique in that the 3MLCT state has a very long lived luminescence (approximately 50 μs in degassed CH3CN). Luminescence decays for both pyrene containing complexes can be fit as double exponentials, indicating that the 3MLCT and 3(π → π*) states are not in equilibrium. Analysis of decays obtained at several temperatures reveal that energy transfer is slower than relaxation of the 3MLCT state but more rapid than decay of the pyrene localized 3(π → π*) state. The results also suggest that electronic coupling between the two states is weak despite the fact that the two chromophores are separated by a single covalent bond.
De la recherche familiale et prosopographique dans les sources juridiques et commerciales de la fin du Moyen Age en Allemagne (1990)

Monnet Pierre. De la recherche familiale et prosopographique dans les sources juridiques et commerciales de la fin du Moyen Age en Allemagne. In: Médiévales, n°19, 1990. Liens de famille. Vivre et choisir sa parenté, sous la direction de Christiane Klapisch-Zuber . pp. 91-96.
Automatic local effect of window/level on 3D scale-space ellipsoidal filtering on run-off-arteries from white blood magnetic resonance angiography (2003)

Pre-filtering is a critical step in 3D segmentation of a blood vessel and its display. This paper presents the local effect of window/level over the 3D scale-space approach for filtering the white blood angiographic volumes and its implementation issues. The raw MR angiographic volume is first converted to an isotropic volume, then the window/level is automatically adjusted slice by slice and a composite volume is generated. 3D edges are then generated using separable Gaussian derivative convolution with known scales. The edge volume is then run by the directional processor at each voxel where the eigenvalues of the 3D ellipsoid are computed. The vessel score per voxel is then estimated based on these three eigenvalues which suppress the non-vasculature and background structures, yielding the filtered volume. The filtered volume is ray-cast to generate the maximum intensity projection images for display. The performance of the system is evaluated by computing the mean, variance, SNR and CNR images. We compare the filtering results with and without the usage of the local effect of window/level over 3D scale-space ellipsoidal filtering. We show that the automatic window/level is effective in detecting small vessels which are otherwise difficult to extrapolate. The system was run over 20 patient studies from different parts of the body such as brain, abdomen, kidney, knee, and ankle. The computer program takes around 150 seconds of processing time per study for a study with a data size of 512 /spl times/ 512 /spl times/ 194, which includes complete performance evaluation.
Spectrophotometric Investigation of Reaction of Titanium with Chromotropic Acid (1953)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpectrophotometric Investigation of Reaction of Titanium with Chromotropic AcidW. W. Brandt and A. E. PreiserCite this: Anal. Chem. 1953, 25, 4, 567–571Publication Date (Print):April 20, 1953Publication History Published online1 May 2002Published inissue 20 April 1953https://pubs.acs.org/doi/10.1021/ac60076a009https://doi.org/10.1021/ac60076a009research-articleACS PublicationsRequest reuse permissionsArticle Views108Altmetric-Citations21LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Quantum Compiler Optimizations (2012)

A quantum computer consists of a set of quantum bits upon which operations called gates are applied to perform computations. In order to perform quantum algorithms, physicists would like to design arbitrary gates to apply to quantum bits. However, the physical limitations of the quantum computing device restrict the set of gates that physicists are able to apply. Thus, they must compose a sequence of gates from the permitted gate set, which approximates the gate they wish to apply - a process called quantum compiling. Austin Fowler proposes a method that finds optimal gate sequences in exponential time, but which is tractable for common problems. In this paper, I present several optimizations to this algorithm. While my optimizations do not improve its overall exponential behavior, they improve its empirical performance by one to two orders of magnitude.
Theoretical analysis of some contemporary issues on wire-array Z-pinch (2009)

First and foremost I would like to thank my advisor, Professor Y. Y. Lau. Without his guidance this thesis would not have been possible. Throughout my graduate studies, he has showed me how to attack difficult problems and get meaningful results. His insights and experiences are invaluable. He is also a great teacher from whom I learned a great deal from not just academically, but lessons in life as well. I am grateful to have him as my advisor. I thank Professor Ronald Gilgenbach for his many useful classes on plasma physics, especially allowing me to teach the plasma laboratory course. The experience has allowed me to both learn how to run an experiment as well as acquire skills for teaching. His insights on how to conduct experiments are also invaluable, from my time spending with him, I learned how to interact and discuss problems with experimentalist. I thank all the professors who taught me throughout my college careers, from each of them I have obtained different skills that will help me succeed both professionally and personally. I thank Dr. Edmund Yu from Sandia National Laboratories for his
SWCNT-Supported Amorphous Gallium Sulfide as a New High-Performance Anode for Lithium-Ion Batteries (2013)

Abstract not Available.
Pharmacokinetics of four different brands of colistimethate and formed colistin in rats (2013)

This is the first study to demonstrate that although different brands of CMS from various parts of the world have similar elemental compositions, they lead to different exposures to the microbiologically active formed colistin. The study has significant implications for the interpretation of pharmacological studies of CMS conducted in different parts of the world.
Dynamics of Bio‐Oss<sup>®</sup> Collagen incorporation in fresh extraction wounds: an experimental study in the dog (2009)

It was demonstrated that the incorporation of Bio-Oss in the tissue that formed in an extraction wound involved a series of different processes.
Nucleotide-promoted Release of hMutSα from Heteroduplex DNA Is Consistent with an ATP-dependent Translocation Mechanism (1998)

ATP hydrolysis by bacterial and eukaryotic MutS activities is required for their function in mismatch correction, and two different models for the role of ATP in MutS function have been proposed. In the translocation model, based on study of bacterial MutS, ATP binding reduces affinity of the protein for a mismatch and activates secondary DNA binding sites that are subsequently used for movement of the protein along the helix contour in a reaction dependent on nucleotide hydrolysis (Allen, D. J., Makhov, A., Grilley, M., Taylor, J., Thresher, R., Modrich, P., and Griffith, J. D. (1997) EMBO J. 16, 4467-4476). The molecular switch model, based on study of human MutSalpha, invokes mismatch recognition by the MutSalpha.ADP complex. After recruitment of downstream repair activities to the MutSalpha.mismatch complex, ATP binding results in release of MutSalpha from the heteroduplex (Gradia, S., Acharya, S., and Fishel, R.(1997) Cell 91, 995-1005). To further clarify the function of ATP binding and hydrolysis in human MutSalpha action, we evaluated the effects of ATP, ADP, and nonhydrolyzable ATP analogs on the lifetime of protein.DNA complexes. All of these nucleotides were found to increase the rate of dissociation of MutSalpha from oligonucleotide heteroduplexes. These experiments also showed that ADP is not required for mismatch recognition by MutSalpha, but that the nucleotide alters the dynamics of formation and dissociation of specific complexes. Analysis of the mechanism of ATP-promoted dissociation of MutSalpha from a 200-base pair heteroduplex demonstrated that dissociation occurs at DNA ends in a reaction dependent on ATP hydrolysis, implying that release from this molecule involves movement of the protein along the helix contour as predicted for a translocation mechanism. In order to reconcile the relatively large rate of movement of MutS homologs along the helix with their modest rate of ATP hydrolysis, we propose a novel mechanism for protein translocation along DNA that supports directional movement over long distances with minimal energy input.
Metal-Free Arylation of Ethyl Acetoacetate with Hypervalent Diaryliodonium Salts: An Immediate Access to Diverse 3-Aryl-4(1<i>H</i>)-Quinolones (2015)

A clean arylation protocol of ethyl acetoacetate was developed using hypervalent diaryliodonium salts under mild and metal-free conditions. The scope of the reaction, using symmetric and unsymmetric iodonium salts with varying sterics and electronics, was examined. Further, this method has been applied for the synthesis of antimalarial compound ELQ-300, which is currently in preclinical development.
THE HERMENEUTICS OF EDUCATIONAL CHOICE (1989)

Part 1: Rival Theories Compared Economics is, in the Robbinsian definition, the science of choice. Economic models of choice are metaphors, encapsulating in abstract figures (lexical or mathematical), the elements of a unique relationship between ends and means. In the view of Austrian economists, this relationship is essentially fictional: It is constructed by the chooser in the moment of choice and embodies his momentary valuation of a particular course of action, seemingly feasible, seemingly the one thing necessary for the enjoyment of some imagined rewards, and seeming to require the surrender of resources deemed in that moment to be at the chooser's disposal. Choice is a subjective affair. It is also, in a sense which may be unique and proper to each actor, an affair fraught with novelty, originality, and the inescapable drive to realise the best of what is apparently possible. Choosers maximise differently and in their own way.
Ultraslow Group Velocity and Enhanced Nonlinear Optical Effects in a Coherently Driven Hot Atomic Gas (1999)

We report the observation of small group velocities of order 90 m/s and large group delays of greater than 0.26 ms, in an optically dense hot rubidium gas ( $\ensuremath{\approx}360\mathrm{K}$). Media of this kind yield strong nonlinear interactions between very weak optical fields and very sharp spectral features. The result is in agreement with previous studies on nonlinear spectroscopy of dense coherent media.
Challenges in Distance Bounding (2015)

Smartcard-based protocols represent an increasingly large share of the wireless authentication market, from contactless payments to remote car unlocking. Unfortunately, relay attacks pose a significant threat to these wireless solutions. However, this risk can be mitigated through the use of distance-bounding protocols. The authors discuss the core challenges of distance bounding, in terms of both theoretical and practical considerations, focusing on their security and the difficulties encountered in their design and implementation. The authors present their vision of the future of these protocols and of the possible paths toward their secure deployment.
Study of a new physical layer encryption concept (2008)

Physical layer encryption is taking a significant importance in securing wireless networks. In this paper, an efficient physical layer encryption is proposed. It relies on the implementation of OFB mode just after the error coding process. The significant advantage of this implementation is that it hides the entire Mac frame. In order to reduce the overhead power consumption at the receiver, an identification mechanism is presented. This security solution is valuable in terms of location privacy and attack prevention. The provided results in this paper prove that this solution does not have any influence on the encoder/decoder functionalities.
A Variable Grain Logic Cell Architecture for Reconfigurable Logic Cores (2007)

Reconfigurable Logic Devices are classified as the fine-grained or coarse-grained type on the basis of their basic logic cell architecture. In general, each architecture has its own merit; therefore, it is difficult to achieve a balance between the operation speed and implementation area in various applications. In this paper, we propose a Variable Grain Logic Cell (VGLC) architecture, which consists of a 4-bit ripple carry adder with configuration memory bits and also develop technology mapping tool. Its key feature is the variable granularity being a trade-off between coarse-grained and fine-grained types required for the implementation arithmetic and random logic, respectively. As a result, critical path delay, and number of configuration memory bits are reduced by 49.7%, and 48.5%, respectively, in the benchmark circuits.
Divorcing Money from Monetary Policy (2008)

Many central banks implement monetary policy in a way that maintains a tight link between the stock of money and the short-term interest rate. In particular, their implementation procedures require that the supply of reserve balances be set precisely in order to implement the target interest rate. Because bank reserves play other key roles in the economy, this link can create tensions with other important objectives, especially in times of acute market stress. This article considers an alternative approach to monetary policy implementation -- known as a \\"floor system\\" -- that can reduce or even eliminate these tensions. The authors explain how this approach, in which the central bank pays interest on reserves at the target interest rate, \\"divorces\\" the supply of money from the conduct of monetary policy. The quantity of bank reserves can then be set according to the payment or liquidity needs of financial markets. By removing the opportunity cost of holding reserves, the floor system also encourages the efficient allocation of resources in the economy.
The ecology of Campylobacter jejuni in avian and human hosts and in the environment (2002)

Campylobacter jejuni, and its close relative C. coli, are highly successful bacteria colonizing the intestinal mucosa of a wide range of avian and animal hosts, including humans. In general, this colonization is either as a commensal, as in birds, or is an asymptomatic transient infection, as in livestock and in humans in endemic regions. However, in susceptible human populations, infection causes acute bacterial enteritis. The ecology of the organism for each outcome of colonization is considered, and evidence suggests that disease symptoms reflect the unfortunate consequences of the expression of bacterial factors associated with adaptation to the host gut environment. Susceptibility to disease appears to be associated with lack of acquired immunity. Although campylobacters do not grow outside the host, they can remain viable for long periods in water, foods, etc. Under such conditions, the organisms adapt to numerous hostile environmental stresses. Although such stressed organisms may be viable, the infectivity of surviving bacteria becomes severely compromised over time. Thus, the comparison of Campylobacter ecology in different environments suggests that increasing trends in human campylobacteriosis represent an unfortunate consequence of: decreasing human immunity because of reduced exposure to stress-compromised organisms; intensive farming practices creating monocultures of some strains; and improved processing and retail practices increasing the viability of campylobacters in food reaching the consumer.