gebhart/patrepeval huggingface dataset:
Specific interaction of the diastereomers 7(R)‐ and 7(S)‐tetrahydrobiopterin with phenylalanine hydroxylase: implications for understanding primapterinuria and vitiligo (2006)

Pterin-4a-carbinolamine dehydratase (PCD) is an essential component of the phenylalanine hydroxylase (PAH) system, catalyzing the regeneration of the essential cofactor 6(R)-L-erythro-5,6,7,8-tetrahydrobiopterin [6(R)BH4]. Mutations in PCD or its deactivation by hydrogen peroxide result in the generation of 7(R,S)BH4, which is a potent inhibitor of PAH that has been implicated in primapterinuria, a variant form of phenylketonuria, and in the skin depigmentation disorder vitiligo. We have synthesized and separated the 7(R) and 7(S) diastereomers confirming their structure by NMR. Both 7(R)- and 7(S)BH4 function as poor cofactors for PAH, whereas only 7(S)BH4 acts as a potent competitive inhibitor vs. 6(R)BH4 (Ki=2.3-4.9 microM). Kinetic and binding studies, as well as characterization of the pterin-enzyme complexes by fluorescence spectroscopy, revealed that the inhibitory effects of 7(R,S)BH4 on PAH are in fact specifically based on 7(S)BH4 binding. The molecular dynamics simulated structures of the pterin-PAH complexes indicate that 7(S)BH4 inhibition is due to its interaction with the polar region at the pterin binding site close to Ser-251, whereas its low efficiency as cofactor is related to a suboptimal positioning toward the catalytic iron. 7(S)BH4 is not an inhibitor for tyrosine hydroxylase (TH) in the physiological range, presumably due to the replacement of Ser-251 by the corresponding Ala297. Taken together, our results identified structural determinants for the specific regulation of PAH and TH by 7(S)BH4, which in turn aid in the understanding of primapterinuria and acute vitiligo.
Precise Top View Image Generation without Global Metric Information (2008)

We describe a practical and precise calibration method for generating a top view image that is transformed so that a planar object such as the road can be observed from a direction perpendicular to its surface. The geometric relation between the input and output images is described by a 3×3 homography matrix. Conventional methods use large planar calibration patterns to achieve precise transformations. The proposed method uses much smaller element patterns that are placed in arbitrary positions within the view of the camera. One of the patterns is used to obtain an initial homography. Then, the information from all of the patterns is used by a non-linear optimization scheme to reach a global optimum homography. The experiment done to evaluate the method showed that the precision of the proposed method is comparable to that of the conventional method where a large calibration pattern is used, making it more practical for automotive applications.
Efficient routing in optical networks (1996)

This paper studies the problem of dedicating routes to connections in optical networks. In optical networks, the vast bandwidth available in an optical fiber is utilized by partitioning it into several channels, each at a different optical wavelength. A connection between two nodes is assigned a specific wavelength, with the constraint that no two connections sharing a link in the network can be assigned the same wavelength. This paper considers optical networks with and without switches, and different types of routing in these networks. It presents optimal or near-optimal constructions of optical networks in these cases and algorithms for routing connections, specifically permutation routing for the networks constructed here.
Comparison of Interference Effects for Manganese in Constant Temperature vs Pulse-Type Electrothermal Atomization (1979)

The application of electrothermal atomization techniques for atomic absorption spectroscopy has increased many fold in recent years. Along with this widespread application, matrix interferences in pulse-type electrothermal atomizers have been observed. Until recently, very few interference studies have involved constant temperature electrothermal atomizers. In this paper a comparison is made of interferences in pulse-type vs constant temperature atmoziers for various metal chlorides on the Mn atomic absorption signal. The results show no interferences in the constant temperature system while significant matrix interferences are observed in the pulse type unit. It is proposed that the observed differences are due mainly to the rate at which volatilized analyte attains atomization temperature and the residence time in the hot environment.
Optimal control strategy for dividend-payments in a risk model with stochastic premiums (2014)

We consider a discrete-time risk model. It is assumed that premiums received in each time period are mutually independent and identically distributed random variables, and the probability of claim occurrence in any time period is related to the premium received in corresponding period. We discuss the optimal dividend strategy. Our method is mainly to transform the value function and use fixed point theory. We obtain some properties of the optimal dividend strategy, and offer high efficiency algorithms for obtaining the optimal strategy and the optimal value function.
Architecture for ultra-low power multi-channel transmitters for Body Area Networks using RF resonators (2011)

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.
Design and fabrication of MEMS devices using the integration of MUMPs, trench-refilled molding, DRIE and bulk silicon etching processes (2004)

This work integrates multi-depth DRIE etching, trench-refilled molding, two poly-Si layers MUMPs and bulk releasing to improve the variety and performance of MEMS devices. In summary, the present fabrication process, named MOSBE II, has three merits. First, this process can monolithically fabricate and integrate poly-Si thin-film structures with different thicknesses and stiffnesses, such as the flexible spring and the stiff mirror plate. Second, multi-depth structures, such as vertical comb electrodes, are available from the DRIE processes. Third, a cavity under the micromachined device is provided by the bulk silicon etching process, so that a large out-of-plane motion is allowed. In application, an optical scanner driven by the self-aligned vertical comb actuator was demonstrated. The poly-Si micromachined components fabricated by MOSBE II can further integrate with the MUMPs devices to establish a more powerful MOEMS platform.
Retrieving Similar X-Ray Images from Big Image Data Using Radon Barcodes with Single Projections (2017)

The idea of Radon barcodes (RBC) has been introduced recently. In this paper, we propose a content-based image retrieval approach for big datasets based on Radon barcodes. Our method (Single Projection Radon Barcode, or SP-RBC) uses only a few Radon single projections for each image as global features that can serve as a basis for weak learners. This is our most important contribution in this work, which improves the results of the RBC considerably. As a matter of fact, only one projection of an image, as short as a single SURF feature vector, can already achieve acceptable results. Nevertheless, using multiple projections in a long vector will not deliver anticipated improvements. To exploit the information inherent in each projection, our method uses the outcome of each projection separately and then applies more precise local search on the small subset of retrieved images. We have tested our method using IRMA 2009 dataset a with 14,400 x-ray images as part of imageCLEF initiative. Our approach leads to a substantial decrease in the error rate in comparison with other non-learning methods.
Nicotinamide Overcomes Pluripotency Deficits and Reprogramming Barriers (2013)

Abstract Crosstalk between intracellular signaling pathways has been extensively studied to understand the pluripotency of human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells (hiPSCs); however, the contribution of NAD+-dependent pathways remains largely unknown. Here, we show that NAD+ depletion by FK866 (a potent inhibitor of NAD+ biosynthesis) was fatal in hPSCs, particularly when deriving pluripotent cells from somatic cells and maintaining pluripotency. NAD and its precursors (nicotinamide [NAM] and nicotinic acid) fully replenished the NAD+ depletion by FK866 in hPSCs. However, only NAM effectively enhanced the reprogramming efficiency and kinetics of hiPSC generation and was also significantly advantageous for the maintenance of undifferentiated hPSCs. Our molecular and functional studies reveal that NAM lowers the barriers to reprogramming by accelerating cell proliferation and protecting cells from apoptosis and senescence by alleviating oxidative stress, reactive oxygen species accumulation, and subsequent mitochondrial membrane potential collapse. We provide evidence that the positive effects of NAM (occurring at concentrations well above the physiological range) on pluripotency control are molecularly associated with the repression of p53, p21, and p16. Our findings establish that adequate intracellular NAD+ content is crucial for pluripotency; the distinct effects of NAM on pluripotency may be dependent not only on its metabolic advantage as a NAD+ precursor but also on the ability of NAM to enhance resistance to cellular stress.
Callus Initiation and Regeneration in Mentha (1990)

Plant regeneration from callus cultures of mint depended on expiant source, genotype, and culture medium components. Mature embryos, seedling and flower parts, as well as chilled or desiccated immature embryos of peppermint (Mentha piperita L.) and spearmint (Mentha spicata L.) were cultured on a Murashige-Skoog medium containing various combinations of growth factors. Shoots regenerated from callus that developed either on mature peppermint embryos cultured on medium that contained BA at 0.5 mg·liter -1 and NAA at 0.5 mg·liter -1 or on immature peppermint embryos (chilled at SC for 0.6 day or nonchilled) cultured on basal medium containing BA at 1 mg·liter -1 and TIBA at 1 mg·liter -1 Shoots were proliferated, rooted, and acclimated. with 100% survival under greenhouse conditions. Chemical names used: N-(phenylmethyl) -1H-purin-6-amine (BA); 1-naphthaleneacetic acid (NAA); 2,3,5-triiodobenzoic acid (TIBA).
Tree-Based Broadcasting in Multihop Radio Networks (1987)

This paper considers the issue of broadcasting protocols in multihop radio networks. The objective of a broadcasting protocol is to deliver the broadcasted message to all network nodes. To efficiently achieve this objective the broad- casting protocol in this paper utilizes two basic properties of the multihop radio network. One is the broadcast nature of the radio which allows every single trasmission to reach all nodes that are in line of sight and within range of the transmitting node. The other, spatial reuse of the radio channel, which due to the multihop nature of the network allows multiple simultaneous transmissions to be received correctly. The proposed protocol incorporates these properties to obtain a collision free forwarding of the broadcasted message on a tree. Centralized and distributed algorithms for the tree construction are presented. The obtained trees are unique in incorporating radio oriented time ordering as part of their definition. In this way multiple copies of one or more broadcasted messages can be transmitted simultaneously without collision, requiring only a small number of message transmissions. Consequently, the protocol not only guarantees that the broadcasted message reaches all network nodes in bounded time, but also ensures that the broadcasting activity will use only limited channel bandwidth and node memory. The proposed broadcast protocol thus possesses the advantages of TDM solutions while allowing the channel bandwidth to be shared, concurrently with the broadcast, with other transmission activities as dictated, for instance, by data link protocols. Some NP-completeness proofs are also given.
An Efficient Synthesis of Pyrrolo[2,1-<i>c</i>][1,4]benzodiazepine. Synthesis of the Antibiotic DC-81 (2001)

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTAn Efficient Synthesis of Pyrrolo[2,1-c][1,4]benzodiazepine. Synthesis of the Antibiotic DC-81Wan-Ping Hu, Jeh-Jeng Wang, Fu-Lung Lin, Yu-Chen Lin, Shinne-Ren Lin, and Mei-Hui HsuView Author Information School of Chemistry, Kaohsiung Medical University, Kaohsiung City 807, Taiwan, R.O.C. [email protected]Cite this: J. Org. Chem. 2001, 66, 8, 2881–2883Publication Date (Web):March 20, 2001Publication History Received16 January 2001Published online20 March 2001Published inissue 1 April 2001https://pubs.acs.org/doi/10.1021/jo010043dhttps://doi.org/10.1021/jo010043dbrief-reportACS PublicationsCopyright © 2001 American Chemical SocietyRequest reuse permissionsArticle Views1118Altmetric-Citations36LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Anions,Antimicrobial agents,Chemical synthesis,Materials,Organic synthesis Get e-Alerts
A STUDY OF AMINO AND OXIMO DERIVATIVES OF THYMOQUINONE<sup>1</sup> (1923)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA STUDY OF AMINO AND OXIMO DERIVATIVES OF THYMOQUINONE1Ralph M. HixonCite this: J. Am. Chem. Soc. 1923, 45, 10, 2333–2341Publication Date (Print):October 1, 1923Publication History Published online1 May 2002Published inissue 1 October 1923https://pubs.acs.org/doi/10.1021/ja01663a014https://doi.org/10.1021/ja01663a014research-articleACS PublicationsRequest reuse permissionsArticle Views95Altmetric-Citations-LEARN 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
Role of nitrogen incorporation into Al<sub>2</sub>O<sub>3</sub>-based resistive random-access memory (2014)

We theoretically study the role of nitrogen incorporation into Al2O3-based resistive random-access memory (ReRAM) by using first-principles calculations. In ReRAM devices, the oxygen vacancy (VO) has been believed to be the origin of ON–OFF switching. We reveal that the VO formation energy is significantly reduced by nitrogen incorporation into Al2O3, resulting in a forming-free ReRAM device. Moreover, nitrogen atoms tend to favorably couple with oxygen vacancies, stabilizing the conductive filament by suppression of VO diffusion. Accordingly, nitrogen incorporation improves the quality of Al2O3-based ReRAM devices.
Hierarchical Multiscale Recurrent Neural Networks (2016)

Learning both hierarchical and temporal representation has been among the long-standing challenges of recurrent neural networks. Multiscale recurrent neural networks have been considered as a promising approach to resolve this issue, yet there has been a lack of empirical evidence showing that this type of models can actually capture the temporal dependencies by discovering the latent hierarchical structure of the sequence. In this paper, we propose a novel multiscale approach, called the hierarchical multiscale recurrent neural networks, which can capture the latent hierarchical structure in the sequence by encoding the temporal dependencies with different timescales using a novel update mechanism. We show some evidence that our proposed multiscale architecture can discover underlying hierarchical structure in the sequences without using explicit boundary information. We evaluate our proposed model on character-level language modelling and handwriting sequence modelling.
Local Authentication with Bluetooth enabled Mobile Devices (2005)

As the processing power of mobile devices such as PDAs and smartphones increase they constitute the target platforms for new value-added services and applications and excellent candidates for personal trusted devices (PTDs). Furthermore, handheld devices are increasingly networked and thus provide a natural and ubiquitous token for authentication purposes. This paper presents a framework and prototype system for exploiting these facts. A Bluetooth-enabled smartphone is used to protect a laptop from unauthorised access with an approach that improves convenience and usability from the user's perspective. The main building blocks are a Diffie-Hellmann based two-party key agreement protocol with authentication mechanisms based on Java midlets and low-entropy human memorable passwords. The results are readily extended to other environments such as payment transactions, remote control of appliances and services, transactions on unattended dispensers of goods such as parking meters, petrol stations, etc
Wide Band Receiving Characteristics of Piezo-Rubber Hydrophone (1992)

The hydrostatic piezoelectric properties and the receiving characteristics of Piezo-Rubber hydrophones are investigated. Piezo-Rubber is piezoelectric composite material consisting of PbTiO 3 and chloroprene rubber. The Piezo-Rubber hydrophones have almost flat frequency characteristics with some variation observed in the receiving characteristics. The relationship between this variation and the transverse resonance mode of Piezo-Rubber plate is discussed. In addition, the receiving characteristics of large-area Piezo-Rubber hydrophones and the Piezo-Rubber frequency constants calculated from resonant frequencies are discussed.
Power-factor metering gains new interest (1980)

The combined effect of increased energy costs, advances in digital metering techniques, and regulatory pressures is stimulating utility interest in charging smaller customers the full cost of their burden on the electric system, by metering reactive power and billing for poor power factor. Oklahoma Gas and Electric Co. adopted the Q-meter method, made practical with the advent of magnetic-tape metering. Digital metering and new techniques now being developed will add more options for utilities interested in metering power factor. There are three commonly used methods of determining power factor, all of which require the use of the standard induction watthour meter, plus at least one other meter, to obtain a second value in the power triangle. In all cases, the third value, if required, is obtained by calculation.
Polymerizable Esters of Lactic Acid. α-Carbalkoxyethyl Acrylates and Methacrylates (1945)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolymerizable Esters of Lactic Acid. α-Carbalkoxyethyl Acrylates and MethacrylatesC. E. Rehberg, Marion B. Dixon, and C. H. FisherCite this: J. Am. Chem. Soc. 1945, 67, 2, 208–210Publication Date (Print):February 1, 1945Publication History Published online1 May 2002Published inissue 1 February 1945https://doi.org/10.1021/ja01218a019RIGHTS & PERMISSIONSArticle Views525Altmetric-Citations25LEARN 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 InReddit PDF (428 KB) Get e-Alerts Get e-Alerts
[Structure and function of TRAP]. (1994)

Thyroid hormone receptor (THR) binds to specific thyroid hormone response element (TRE). Using an electrophoretic mobility shift assay (gel-shift), Murray and Towel recently found that cell nuclear extracts enhance the binding of THR to TRE. This protein has been designated T3 receptor auxiliary protein (TRAP). Retinoid X receptors (RXR alpha, beta) can function as TRAP. TRAP forms a heterodimer with THR through the ligand binding domain of both receptors. This area contains leucine zipper like heptad repeats which can form amphipathic alpha-helixes. The ligand (9-cis retinoic acid) of RXR may or may not synergistically increase T3/THR-mediated transactivation. The effects of 9-cis retinoic acid depends on the nature of the TRE. One of the functions of TRAP may be to alter the expression of T3-regulated genes.
Semiconducting polymer LEDs (2002)

Technologies based on organic semiconductors may answer the increasing demands that consumers make in the areas of large-area electronics, lightweight displays, and portable computing. Advances in scientific understanding, technology, and device performance have occurred particularly rapidly in the area of polymer light-emitting diodes (LEDs). Material properties and economic considerations suggest that polymer LEDs are the devices most likely to win the race to applications that produce light on inorganic substrates such as glass and silicon, as well as plastic substrates. The field of semiconducting polymers has its root in the 1977 discovery of the semiconducting properties of polyacetylene1. This breakthrough earned Alan Heeger, Alan MacDiarmid, and Hideki Shirakawa the 2000 Nobel Prize in Chemistry for ‘the discovery and development of conductive polymers’2, 3, 4, 5. Other review articles capture how more than two decades of developments in the physical and chemical understanding of these novel materials has led to new device applications as active and passive electronic and optoelectronic devices ranging from diodes and transistors to polymer LEDs, photodiodes, lasers, and solar cells6, 7, 8, 9, 10, 11. Much interest in plastic devices derives from the opportunities to use clever control of polymer structure combined with relatively economical polymer synthesis and processing techniques to obtain simultaneous control over electronic, optical, chemical, and mechanical features5. This article focuses on the advances leading to polymer LEDs12, 13, 14.