cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
First-Principles Theory of Multipolar Order in Neptunium Dioxide
Creators: name: Suzuki, Michi-To
name: Magnani, Nicola
name: Oppeneer, Peter M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We provide a first-principle, materials-specific theory of multipolar order and superexchange in NpO$_2$ by means of a non-collinear local-density approximation +$U$ (LDA+$U$) method. Our calculations offer a precise microscopic description of the triple-$q$-antiferro ordered phase in the absence of any dipolar moment. We find that, while the most common non-dipolar degrees of freedom (e.g., electric quadrupoles and magnetic octupoles) are active in the ordered phase, both the usually neglected higher-order multipoles (electric hexadecapoles and magnetic triakontadipoles) have at least an equally significant effect.
description: 4 pages, 3 figures
Thermal Dileptons from Hot and Dense Strongly Interacting Matter
Creators: name: Specht, Hans J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The NA60 experiment at the CERN SPS has studied muon-pair production in 158A GeV In-In collisions. The unprecedented precision of the data has allowed to isolate a strong excess of pairs above the known sources in the whole invariant mass region 0.2 rho -> mu+mu- dominates. The associated space-time averaged rho spectral function shows a nearly diverging width in approaching chiral symmetry restoration, but essentially no shift in mass. Some in-medium effects are also seen for the omega, but not for the phi. For M>1 GeV, the average temperature associated with the mass spectrum is about 200 MeV, considerably above T_c=170 MeV, implying a transition to dominantly partonic emission sources in this region. The transition itself is mirrored by a large jump-like drop in the inverse slope of the transverse mass spectra around 1 GeV.
description: 10 pages, 6 figures, Proceedings of Chiral 2010 (Valencia, June 21-24, 2010)
Natural phosphodiesterase 5 (PDE5) inhibitors: a computational approach
Creators: name: Ongaro, Alberto
name: Zagotto, Giuseppe
name: Memo, Maurizio
name: Gianoncelli, Alessandra
name: Ribaudo, Giovanni
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Medicine
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences

description: In 1998, sildenafil was marketed as the first FDA-approved oral drug for the treatment of erectile dysfunction (ED). During the last two decades, the commercialization of other synthetic phosphodiesterase 5 (PDE5) inhibitors has been paralleled by the rise of remedies based on natural molecules from different chemical classes (flavonoids, polyphenols and alkaloids in general). In this work, a set of in silico tools were applied to study a panel of 30 natural compounds claimed to be effective against ED in the scientific literature or in folk medicine. First, pharmacokinetic properties were analysed to exclude the compounds lacking in specific drug-like features. Estimated binding energy for PDE5 and selectivity towards other PDE isoforms were then considered to highlight some promising molecules. Finally, a detailed structural investigation of the interaction pattern with PDE in comparison with sildenafil was conducted for the best performing compound of the set.
Anti-inflammatory and sedative activities of Peperomia galioides: in vivo studies in mice
Creators: name: Wilches, Isabel
name: Jiménez-Castillo, Priscila
name: Cuzco, Nancy
name: Clos, M. Victoria
name: Jiménez-Altayó, Francesc
name: Peñaherrera, Eugenia
name: Jerves-Andrade, Lourdes
name: Tobar, Vladimiro
name: Heyden, Yvan Vander
name: Leon-Tamariz, Fabián
name: Vila, Elisabet
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Space Science
subject: Microbiology
subject: FOS: Biological sciences
subject: Neuroscience
subject: Physiology
subject: Pharmacology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Aerial parts (leaves, flowers, stem) of Peperomia galioides extract administered to mice, was used to confirm its anti-inflammatory and sedative folk uses. The anti-inflammatory activity was assessed by croton oil-induced ear oedema and myeloperoxidase (acute inflammation); cotton pellet-induced granuloma (sub-acute inflammation) and Escherichia coli Lipopolysaccharide (LPS) induced inflammation (cellular mediators). The sedative activity was studied by the pentobarbital-induced sleeping time test. Single doses (300 and 600 mg/kg; i.p.) of the extract reduced croton oil-induced ear oedema and myeloperoxidase activity. Six days administration of the extract (300 mg/kg, i.p.) to mice implanted with cotton pellets diminished granuloma formation. LPS (20 mg/kg, i.p.) enhanced plasma nitrites and TNF-α levels that were inhibited by the extract. The duration but not the onset of sleeping time was enhanced by 300 and 600 mg/kg of the extract. Our results show that P. galioides has anti-inflammatory and sedative activities in mice, which validates its traditional use.
Sequential ED-design for binary dose-response experiments
Creators: name: Yu, Xiaoli
Publisher: name: University of British Columbia
Year: 2017

description: Dose-response experiments and subsequent data analyses are often carried out according to optimal designs for the purpose of accurately determining a specific effective dose (ED) level. If the interest is the dose-response relationship over a range of ED levels, many existing optimal designs are not accurate. In this dissertation, we propose a new design procedure, called two-stage sequential ED-design, which directly and simultaneously targets several ED levels. We use a small number of trials to provide a tentative estimation of the model parameters. The doses of the subsequent trials are then selected sequentially, based on the latest model information, to maximize the efficiency of the ED estimation over several ED levels. Although the commonly used logistic and probit models are convenient summaries of the dose-response relationship, they can be too restrictive. We introduce and study a more flexible albeit slightly more complex three-parameter logistic dose-response model. We explore the effectiveness of the sequential ED-design and the D-optimal design under this model, and develop an effective model fitting strategy. We develop a two-step iterative algorithm to compute the maximum likelihood estimate of the model parameters. We prove that the algorithm iteration increases the likelihood value, and therefore will lead to at least a local maximum of the likelihood function. We also study the numerical solution to the D-optimal design for the three-parameter logistic model. Interestingly, all our numerical solutions to the D-optimal design are three-point-support distributions. We also discuss the use of the ED-design when experimental subjects become available in groups. We introduce the group sequential ED-design, and demonstrate how to construct this design. The ED-design has a natural extension to more complex model and can satisfy a broad range of the demands that may arise in applications.
A cold complex chemistry toward the low-mass protostar B1-b: evidence for complex molecule production in ices
Creators: name: Oberg, Karin I.
name: Bottinelli, Sandrine
name: Jorgensen, Jes K.
name: van Dishoeck, Ewine F.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Gas-phase complex organic molecules have been detected toward a range of high- and low-mass star-forming regions at abundances which cannot be explained by any known gas-phase chemistry. Recent laboratory experiments show that UV irradiation of CH3OH-rich ices may be an important mechanism for producing complex molecules and releasing them into the gas-phase. To test this ice formation scenario we mapped the B1-b dust core and nearby protostar in CH3OH gas using the IRAM 30m telescope to identify locations of efficient non-thermal ice desorption. We find three CH3OH abundance peaks tracing two outflows and a quiescent region on the side of the core facing the protostar. The CH3OH gas has a rotational temperature of ~10 K at all locations. The quiescent CH3OH abundance peak and one outflow position were searched for complex molecules. Narrow, 0.6-0.8 km s-1 wide, HCOOCH3 and CH3CHO lines originating in cold gas are clearly detected, CH3OCH3 is tentatively detected and C2H5OH and HOCH2CHO are undetected toward the quiescent core, while no complex molecular lines were found toward the outflow. The core abundances with respect to CH3OH are ~2.3% and 1.1% for HCOOCH3 and CH3CHO, respectively, and the upper limits are 0.7-1.1%, which is similar to most other low-mass sources. The observed complex molecule characteristics toward B1-b and the pre-dominance of HCO-bearing species suggest a cold ice (below 25 K, the sublimation temperature of CO) formation pathway followed by non-thermal desorption through e.g. UV photons traveling through outflow cavities. The observed complex gas composition together with the lack of any evidence of warm gas-phase chemistry provide clear evidence of efficient complex molecule formation in cold interstellar ices.
description: 23 pages, 7 figures, accepted for publication in ApJ
q-Breathers and thermalization in acoustic chains with arbitrary nonlinearity index
Creators: name: Ivanchenko, M. V.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Nonlinearity shapes lattice dynamics affecting vibrational spectrum, transport and thermalization phenomena. Beside breathers and solitons one finds the third fundamental class of nonlinear modes -- $q$-breathers -- periodic orbits in nonlinear lattices, exponentially localized in the reciprocal mode space. To date, the studies of $q$-breathers have been confined to the cubic and quartic nonlinearity in the interaction potential. In this paper we study the case of arbitrary nonlinearity index $γ$ in an acoustic chain. We uncover qualitative difference in the scaling of delocalization and stability thresholds of $q$-breathers with the system size: there exists a critical index $γ^*=6$, below which both thresholds (in nonlinearity strength) tend to zero, and diverge when above. We also demonstrate that this critical index value is decisive for the presence or absense of thermalization. For a generic interaction potential the mode space localized dynamics is determined only by the three lowest order nonlinear terms in the power series expansion.
description: 5 pages, 4 figures
Heavy quark meson spectroscopy at CDF (X(3872) mass and evidence for Y(4140))
Creators: name: Wick, Felix
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: With growing datasets collected by the CDF II experiment, studies of the spectroscopy of mesons containing heavy quarks become more exciting. The CDF experiment has good capabilities in both charm and bottom sector. This capability allowed also to contribute to the study of the zoo of states called X,Y,Z. In this area we present a recent update of the mass measurement of X(3872). The result m(X(3872)) = 3871.61 +- 0.16 +- 0.19 MeV is currently the most precise measurement in the world. In addition, we report evidence for a new narrow resonance, Y(4140), the first to be seen in the J/psi phi decay mode, using 2.7 invfb of exclusive B+ to J/psi phi K+ decays.
description: 5 pages, 8 figures
A Tracking Fiber Detector based on Silicon Photomultipliers for the Kaos Spectrometer
Creators: name: Achenbach, P.
name: Pochodzalla, J.
name: Majos, S. Sánchez
Publisher: name: arXiv
Year: 2011
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: A tracking detector based on two meters long scintillating fibers read out by silicon photomultipliers (SiPM) is being developed for the Kaos spectrometer at the Mainz Microtron MAMI. Results from a prototype setup using 2 mm square fibers and large area SiPM readout are presented. The detection efficiency of such a combination was measured to be between 83 and 100% depending on the threshold on the SiPM amplitude. A Monte Carlo simulation based on a physical model was employed in order to extract the photon detection efficiency of the SiPM devices.
description: Contributed to 2008 IEEE Nuclear Science Symposium, 19-25 October 2008, Dresden, Germany
Overview of the European Underground Facilities
Creators: name: Pandola, L.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Deep underground laboratories are the only places where the extremely low background radiation level required for most experiments looking for rare events in physics and astroparticle physics can be achieved. Underground sites are also the most suitable location for very low background gamma-ray spectrometers, able to assay trace radioactive contaminants. Many operational infrastructures are already available worldwide for science, differing for depth, dimension and rock characteristics. Other underground sites are emerging as potential new laboratories. In this paper the European underground sites are reviewed, giving a particular emphasis on their relative strength and complementarity. A coordination and integration effort among the European Union underground infrastructures was initiated by the EU-funded ILIAS project and proved to be very effective.
description: Prepared for the Proceedings of the Topical Workshop in Low Radioactivity Techniques (Sudbury, Canada), August 28-29, 2010m (LRT2010). To be published on AIP conference proceedings
title: Boomerang Switch in Multiple Rounds. Application to AES Variants and Deoxys
Creators: name: Wang, Haoyang
name: Peyrin, Thomas
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: The boomerang attack is a cryptanalysis technique that allows an attacker to concatenate two short differential characteristics. Several research results (ladder switch, S-box switch, sandwich attack, Boomerang Connectivity Table (BCT), ...) showed that the dependency between these two characteristics at the switching round can have a significant impact on the complexity of the attack, or even potentially invalidate it. In this paper, we revisit the issue of boomerang switching effect, and exploit it in the case where multiple rounds are involved. To support our analysis, we propose a tool called Boomerang Difference Table (BDT), which can be seen as an improvement of the BCT and allows a systematic evaluation of the boomerang switch through multiple rounds. In order to illustrate the power of this technique, we propose a new related-key attack on 10-round AES-256 which requires only 2 simple related-keys and 275 computations. This is a much more realistic scenario than the state-of-the-art 10-round AES-256 attacks, where subkey oracles, or several related-keys and high computational power is needed. Furthermore, we also provide improved attacks against full AES-192 and reduced-round Deoxys.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
Effects of long duration ground motions on the probability of drift exceedance for reinforced concrete frames near the Cascadia Subduction Zone
Creators: name: Chin, David Holl Ling
Publisher: name: University of British Columbia
Year: 2017

description: There are discrepancies in responses when a structure is subjected to short and long duration ground motions. The probability of drift exceedance has been repeated reported to increase under the influence of long duration records. Although the 2015 National Building Code of Canada has probabilistically taken the Cascadia Subduction Zone seismic hazards into considerations, none is known as what might happen to structures designed using this new Code if subjected to a large magnitude subduction earthquake. The answer is found via computer simulation. Following the general approach adopted in the Seismic Retrofit Guidelines 2nd Edition, incremental dynamic analysis is conducted to investigate discrepancies in the probability of drift exceedance for certain building types under both crustal and subduction ground motion records. These ground motions are selected and scaled to match the 2015 uniform hazard spectrum of Victoria, B.C. A simple shear wall model is first examined to generalize the effects of long duration ground motions. Then a similar study on a reinforced concrete frame is conducted to confirm these generalizations. Long duration ground motions seem to cause a higher probability of drift exceedance in moderately ductile buildings. However, no effect is observed in non-ductile and highly ductile buildings. The system internal capability to dissipate seismic energy by means of hysteretic loops is also contributing to the overall probability of drift exceedance. Its effect is more evident in the long duration as there are more load reversal cycles. Results discussion is provided, and potential ways to account for long duration in structural design are recommended.
Exact Solution of Bardeen Black Hole in Einstein-Gauss-Bonnet gravity
Creators: name: Kumar, Amit
name: Singh, Dharm Veer
name: Myrzakulov, Yerlan
name: Yergaliyeva, Gulmira
name: Upadhyay, Sudhaker
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We have obtained a new exact regular black hole solution for the EGB gravity coupled with nonlinear electrodynamics in AdS space. The numerical analysis of horizon structure suggests two horizons exist: Cauchy and event. We also study the thermal properties of this black hole, which satisfy the modified first law of thermodynamics. Moreover, we analyse the local and global stability of the black hole. The $P-V$ criticality and phase transition are also discussed. The critical exponents for the present model exactly match the mean field theory.
description: 22 pages, 22 pages, published in EPJP
The nature of "dark" gamma-ray bursts
Creators: name: Greiner, J.
name: Krühler, T.
name: Klose, S.
name: Afonso, P.
name: Clemens, C.
name: Filgas, R.
name: Hartmann, D. H.
name: Yoldaş, A. Küpcü
name: Nardini, M.
name: Estay, F. Olivares
name: Rau, A.
name: Rossi, A.
name: Schady, P.
name: Updike, A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Context: Thirteen years after the discovery of the first afterglows, the nature of dark gamma-ray bursts (GRB) still eludes explanation: while each ng-duration GRB typically has an X-ray afterglow, optical/NIR emission is only seen for 40-60% of them. Aim: Here we use the afterglow detection statistics of the systematic follow-up observations performed with GROND since mid-2007 in order to derive the fraction of "dark bursts" according to different methods, and to distinguish between various scenarios for "dark bursts". Method: Observations were performed with the 7-channel "Gamma-Ray Optical and Near-infrared Detector" (GROND) at the 2.2m MPI/ESO telescope. We used the afterglow detection rate in dependence on the delay time between GRB and the first GROND exposure. Results: For long-duration Swift bursts with a detected X-ray afterglow, we achieve a 90% (35/39) detection rate of optical/NIR afterglows whenever our observations started within less than 240\,min after the burst. Complementing our GROND data with Swift/XRT spectra we construct broad-band spectral energy distributions and derive rest-frame extinctions. e detect 25-40% "dark bursts", depending on the definition used. The faint optical afterglow emission of "dark bursts" is mainly due to a combination of two contributing factors: (i) moderate intrinsic extinction at moderate redshifts, and (ii) about 22% of "dark" bursts at redshift $>$5.
description: 9 pages, 6 figs, A&A (accepted)
Mosquito larvicidal potential of hydroxy-2-methyl-4H-pyran-4-one (MALTOL) isolated from the methanol root extract of Senecio laetus Edgew. and its in-silico study
Creators: name: Ali, Sofi Imtiyaz
name: Venugopalan, Venkatesalu
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Cancer
subject: Plant Biology

description: In the present study, hydroxy-2-methyl-4H-pyran-4-one was isolated from the methanol root extract of Senecio laetus and was identified by FT-IR, 1H, 13C NMR and GC-MS. The larvicidal potential of the compound 3-hydroxy-2-methyl-4H-pyran-4-one was evaluated against the 4th instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus at concentrations ranging from 20 to 1.25 ppm under laboratory conditions. The compound showed 100% mortality at 20 ppm against all the tested mosquitoe species and the LC50 and LC90 values were 1.22 and 7.25 ppm (An. stephensi), 2.10 and 99.84 ppm (Ae. aegypti) and 3.88 and 12.47 ppm (Cx. quinquefasciatus), respectively after 24 h of exposure period. In silico molecular docking study results reflects that hydroxy-2-methyl-4H-pyran-4-one compound showed highest binding affinity with OBP of Cx. quinquefasciatus (Glide energy score – 7.3 kcal/mol−1). The larvicidal activity of hydroxy-2-methyl-4H-pyran-4-one against tested mosquito species appears interesting and may be developed after toxicological and field evaluation.
title: A General Proof Framework for Recent AES Distinguishers
Creators: name: Boura, Christina
name: Canteaut, Anne
name: Coggia, Daniel
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: In this paper, a new framework is developed for proving and adapting the recently proposed multiple-of-8 property and mixture-differential distinguishers. The above properties are formulated as immediate consequences of an equivalence relation on the input pairs, under which the difference at the output of the round function is invariant. This approach provides a further understanding of these newly developed distinguishers. For example, it clearly shows that the branch number of the linear layer does not influence the validity of the property, on the contrary of what was previously believed. We further provide an extension of the mixture-differential distinguishers and multiple-of-8 property to any SPN and to a larger class of subspaces. These adapted properties can then be exhibited in a systematic way for other ciphers than the AES. We illustrate this with the examples of Midori, Klein, LED and Skinny.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
title: Zero-Correlation Attacks on Tweakable Block Ciphers with Linear Tweakey Expansion
Creators: name: Ankele, Ralph
name: Dobraunig, Christoph
name: Guo, Jian
name: Lambooij, Eran
name: Leander, Gregor
name: Todo, Yosuke
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: The design and analysis of dedicated tweakable block ciphers is a quite recent and very active research field that provides an ongoing stream of new insights. For instance, results of Kranz, Leander, and Wiemer from FSE 2017 show that the addition of a tweak using a linear tweak schedule does not introduce new linear characteristics. In this paper, we consider – to the best of our knowledge – for the first time the effect of the tweak on zero-correlation linear cryptanalysis for ciphers that have a linear tweak schedule. It turns out that the tweak can often be used to get zero-correlation linear hulls covering more rounds compared to just searching zero-correlation linear hulls on the data-path of a cipher. Moreover, this also implies the existence of integral distinguishers on the same number of rounds. We have applied our technique on round reduced versions of Qarma, Mantis, and Skinny. As a result, we can present – to the best of our knowledge – the best attack (with respect to number of rounds) on a round-reduced variant of Qarma.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
title: Related-Tweak Statistical Saturation Cryptanalysis and Its Application on QARMA
Creators: name: Li, Muzhou
name: Hu, Kai
name: Wang, Meiqin
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: Statistical saturation attack takes advantage of a set of plaintext with some bits fixed while the others vary randomly, and then track the evolution of a non-uniform plaintext distribution through the cipher. Previous statistical saturation attacks are all implemented under single-key setting, and there is no public attack models under related-key/tweak setting. In this paper, we propose a new cryptanalytic method which can be seen as related-key/tweak statistical saturation attack by revealing the link between the related-key/tweak statistical saturation distinguishers and KDIB (Key Difference Invariant Bias) / TDIB (Tweak Difference Invariant Bias) ones. KDIB cryptanalysis was proposed by Bogdanov et al. at ASIACRYPT’13 and utilizes the property that there can exist linear trails such that their biases are deterministically invariant under key difference. And this method can be easily extended to TDIB distinguishers if the tweak is also alternated. The link between them provides a new and more efficient way to find related-key/tweak statistical saturation distinguishers in ciphers. Thereafter, an automatic searching algorithm for KDIB/TDIB distinguishers is also given in this paper, which can be implemented to find word-level KDIB distinguishers for S-box based key-alternating ciphers. We apply this algorithm to QARMA-64 and give related-tweak statistical saturation attack for 10-round QARMA-64 with outer whitening key. Besides, an 11-round attack on QARMA-128 is also given based on the TDIB technique. Compared with previous public attacks on QARMA including outer whitening key, all attacks presented in this paper are the best ones in terms of the number of rounds.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
A quartz crystal biosensor for measurement in liquids
Creators: name: Kösslinger, C.
name: Drost, S.
name: Aberl, F.
name: Wolf, Hans J.
name: Koch, S.
name: Woias, P.
Publisher: name: Universität Regensburg
Year: 1992
Subjects: subject: 610 Medizin
subject: Biosensing Techniques
subject: Biotechnology
subject: Crystallization
subject: Electronics
subject: Evaluation Studies as Topic
subject: HIV Antibodies/analysis
subject: HIV Antigens
subject: Humans
subject: Immunoassay/methods
subject: Immunosorbent Techniques
subject: Peptides/immunology
subject: Quartz

description: The detection of anti-human immunodeficiency virus (HIV) antibodies by means of synthetic HIV peptide immobilized on a piezoelectric quartz sensor is demonstrated. The measurement set-up consists of an oscillator circuit, a suitably modified AT-cut thickness-shear-mode quartz crystal with gold electrodes, which is housed in a special reaction vessel, and a computer-controlled frequency counter for the registration of the measured frequency values. The quartz crystal is adapted for a steady operation in liquids at a frequency of 20 MHz. In phosphate-buffered saline solution the oscillator reaches a stability of about 0.5 Hz within a few seconds, of about 2 Hz within 10 min and about 30 Hz within 1 h. The frequency shift due to the adsorption of various proteins to the uncoated sensor surface has been investigated. It can be shown that a stable adsorptive binding of proteins to an oscillating gold surface is feasible and can be used for the immobilization of a receptor layer (e.g. HIV peptide). Specific binding of the anti-HIV monoclonal antibody to the HIV peptide immobilized on the quartz sensor is demonstrated. Control experiments show, however, additional unspecific binding. According to the experiments, the Sauerbrey formula gives a sufficiently accurate value for the decrease of the resonant frequency due to adsorption or binding of macromolecular proteins on the quartz crystal surface.
title: General Diffusion Analysis: How to Find Optimal Permutations for Generalized Type-II Feistel Schemes
Creators: name: Cauchois, Victor
name: Gomez, Clément
name: Thomas, Gaël
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: Type-II Generalized Feistel Schemes are one of the most popular versions of Generalized Feistel Schemes. Their round function consists in applying a classical Feistel transformation to p sub-blocks of two consecutive words and then shifting the k = 2p words cyclically. The low implementation costs it offers are balanced by a low diffusion, limiting its efficiency. Diffusion of such structures may however be improved by replacing the cyclic shift with a different permutation without any additional implementation cost. In this paper, we study ways to determine permutations with the fastest diffusion called optimal permutations.
To do so, two ideas are used. First, we study the natural equivalence classes of permutations that preserve cryptographic properties; second, we use the representation of permutations as coloured trees.
For both heuristic and historical reasons, we focus first on even-odd permutations, that is, those permutations for which images of even numbers are odd. We derive from their structure an upper bound on the number of their equivalence classes together with a strategy to perform exhaustive searches on classes. We performed those exhaustive searches for sizes k ≤ 24, while previous exhaustive searches on all permutations were limited to k ≤ 16. For sizes beyond the reach of this method, we use tree representations to find permutations with good intermediate diffusion properties. This heuristic leads to an optimal even-odd permutation for k = 26 and best-known results for sizes k = 64 and k = 128.
Finally, we transpose these methods to all permutations. Using a new strategy to exhaust equivalence classes, we perform exhaustive searches on classes for sizes k ≤ 20 whose results confirmed the initial heuristic: there always exist optimal permutations that are even-odd and furthermore for k = 18 all optimal permutations are even-odd permutations.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
Anticholinesterase activity and metabolite profiling of Syagrus romanzoffiana (Cham.) Glassman leaves and fruits via UPLC–QTOF–PDA–MS
Creators: name: El-Hawary, Seham S.
name: Fathy, Fify I.
name: Sleem, Amany A.
name: Morsy, Fatma A.
name: Khadar, Mai S.
name: Mansour, Mai K.
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified

description: The purpose of this study is to provide a complete metabolic profile of the hydroalcoholic extracts of the leaves and fruits of Syagrus romanzoffiana (Cham.) Glassman via UPLC–QTOF–PDA–MS and to evaluate their anticholinesterase activities in a model of Alzheimer disease. The current study has identified 39 metabolites belonging to various chemical classes (i.e. flavonols, phenolic acids, fatty acids, stilbenoids and lignans). While the fatty acids predominated in both leaves and fruits, the stilbenoids were more predominant in leaves. Their neuroprotective effect was comparable to Aricept; the standard drug used in treatment of Alzheimer disease. Both extracts significantly decreased the acetylcholinesterase activity and improved the histopathological changes in the cerebral cortex and cerebellum of rat model of aluminium chloride-induced Alzheimer disease. In light of the current study, Syagrus romanzoffiana (Cham.) Glassman is recommended as promising candidate for palliative treatment in Alzheimer disease through inhibition of the acetylcholinesterase activity.
title: Partitions in the S-Box of Streebog and Kuznyechik
Creators: name: Perrin, Léo
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: Streebog and Kuznyechik are the latest symmetric cryptographic primitives standardized by the Russian GOST. They share the same S-Box, π, whose design process was not described by its authors. In previous works, Biryukov, Perrin and Udovenko recovered two completely different decompositions of this S-Box.
We revisit their results and identify a third decomposition of π. It is an instance of a fairly small family of permutations operating on 2m bits which we call TKlog and which is closely related to finite field logarithms. Its simplicity and the small number of components it uses lead us to claim that it has to be the structure intentionally used by the designers of Streebog and Kuznyechik.
The 2m-bit permutations of this type have a very strong algebraic structure: they map multiplicative cosets of the subfield GF(2m)* to additive cosets of GF(2m)*. Furthermore, the function relating each multiplicative coset to the corresponding additive coset is always essentially the same. To the best of our knowledge, we are the first to expose this very strong algebraic structure.
We also investigate other properties of the TKlog and show in particular that it can always be decomposed in a fashion similar to the first decomposition of Biryukov et al., thus explaining the relation between the two previous decompositions. It also means that it is always possible to implement a TKlog efficiently in hardware and that it always exhibits a visual pattern in its LAT similar to the one present in π. While we could not find attacks based on these new results, we discuss the impact of our work on the security of Streebog and Kuznyechik. To this end, we provide a new simpler representation of the linear layer of Streebog as a matrix multiplication in the exact same field as the one used to define π. We deduce that this matrix interacts in a non-trivial way with the partitions preserved by π.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
title: PEIGEN – a Platform for Evaluation, Implementation, and Generation of S-boxes
Creators: name: Bao, Zhenzhen
name: Guo, Jian
name: Ling, San
name: Sasaki, Yu
Publisher: name: Ruhr-Universität Bochum
Year: 2019

description: In this paper, a platform named PEIGEN is presented to evaluate security, find efficient software/hardware implementations, and generate cryptographic S-boxes. Continuously developed for decades, S-boxes are constantly evolving in terms of the design criteria for both security requirements and software/hardware performances. PEIGEN is aimed to be a platform covering a comprehensive check-list of design criteria of S-boxes appearing in the literature. To do so, the security requirements are first intensively surveyed, existing tools of S-boxes are then comprehensively compared, and finally our platform PEIGEN is presented. The survey part is aimed to be a systematic reference for the theoretical study of S-boxes. The platform is aimed to be an assistant tool for the experimental study and practical use of S-boxes. PEIGEN not only integrates most of the features in existing tools, but also equips with functionalities to evaluate new security-related properties, improves the efficiency of the search algorithms for optimized implementations in several aspects. With the help of this powerful platform, many interesting observations are made in-between the security notations, as well as on the S-boxes used in the existing symmetrickey cryptographic primitives. PEIGEN will become an open platform and welcomes contributions from all parties to help the community to facilitate the research and use of S-boxes.
description: IACR Transactions on Symmetric Cryptology, Volume 2019, Issue 1
Nonlinear dispersion of stationary waves in collisionless plasmas
Creators: name: Dodin, I. Y.
name: Fisch, N. J.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: A nonlinear dispersion of a general stationary wave in collisionless plasma is obtained in a non-differential form from a single-particle oscillation-center Hamiltonian. For electrostatic oscillations in nonmagnetized plasma, considered as a paradigmatic example, the linear dielectric function is generalized, and the trapped particle contribution to the wave frequency shift $Δω$ is found analytically as a function of the wave amplitude $a$. Smooth distributions yield $Δω\sim a^{1/2}$, as usual. However, beam-like distributions of trapped electrons result in different power laws, or even a logarithmic nonlinearity, which are derived as asymptotic limits of the same dispersion relation.
Localized solutions for the finite difference semi-discretization of the wave equation
Creators: name: Marica, Aurora-Mihaela
name: Zuazua, Enrique
Publisher: name: arXiv
Year: 2010
Subjects: subject: Analysis of PDEs (math.AP)
subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: We study the propagation properties of the solutions of the finite-difference space semi-discrete wave equation on an uniform grid of the whole Euclidean space. We provide a construction of high frequency wave packets that propagate along the corresponding bi-characteristic rays of Geometric Optics with a group velocity arbitrarily close to zero. Our analysis is motivated by control theoretical issues. In particular, the continuous wave equation has the so-called observability property: for a sufficiently large time, the total energy of its solutions can be estimated in terms of the energy concentrated in the exterior of a compact set. This fails to be true, uniformly on the mesh-size parameter, for the semi-discrete schemes and the observability constant blows-up at an arbitrarily large polynomial order. Our contribution consists in providing a rigorous derivation of those wave packets and in analyzing their behavior near that ray, by taking into account the subtle added dispersive effects that the numerical scheme introduces.
description: 7 pages, 1 figure
Detecting and handling outlying trajectories in irregularly sampled functional datasets
Creators: name: Gervini, Daniel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: Outlying curves often occur in functional or longitudinal datasets, and can be very influential on parameter estimators and very hard to detect visually. In this article we introduce estimators of the mean and the principal components that are resistant to, and then can be used for detection of, outlying sample trajectories. The estimators are based on reduced-rank t-models and are specifically aimed at sparse and irregularly sampled functional data. The outlier-resistance properties of the estimators and their relative efficiency for noncontaminated data are studied theoretically and by simulation. Applications to the analysis of Internet traffic data and glycated hemoglobin levels in diabetic children are presented.
description: Published in at http://dx.doi.org/10.1214/09-AOAS257 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Phytotoxic and antioxidant effects of dichloromethane fraction of Smilax Brasiliensis Sprengel
Creators: name: Barbosa, Myriam Almeida
name: Fonseca, Juliana Costa
name: Ferraz, Vany
name: Hortência Fonsêca Castro, Ana
name: Alves Rodrigues dos Santos Lima, Luciana
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Physiology
subject: FOS: Biological sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: Sociology
subject: FOS: Sociology
subject: Hematology

description: Dichloromethane (DCM) fraction and sub-fractions obtained from Smilax brasiliensis leaves were examined in order to determine their phytotoxic and antioxidant effects. The dichloromethane fraction was submitted to a preparative layer chromatography leading to seven sub-fractions (DCM1-DCM7). Gas chromatography-mass spectrometry (GC-MS) was performed on the dichloromethane sub-fractions. The DCM sub-fractions presented phytotoxic potential; at a concentration of 125 µg per plate, DCM6 and DCM4 showed the strongest results on Lactuca sativa and Allium cepa, respectively. The DCM fraction and DCM4 sub-fraction were more effective than 2,6-di-tert-butyl-4-methylphenol (BHT) at scavenging the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Analysis by GC-MS showed the presence of methyl palmitate (33.05%) in DCM4 and methyl palmitate (17.29%) and methyl oleate (50.96%) in DCM6, suggesting that the activities exhibited by the sub-fractions may be attributed, at least partially, to these major compounds. These results indicate that the DCM sub-fractions of S. brasiliensis could be used as natural herbicides and antioxidants.
Anti-proliferative effect of pomegranate peel extracts on bovine peripheral blood mononuclear cells (PBMCs)
Creators: name: Mastrogiovanni, Fabio
name: Romani, Annalisa
name: Santi, Luca
name: Lacetera, Nicola
name: Bernini, Roberta
Publisher: name: Taylor & Francis
Year: 2019
Subjects: subject: Biochemistry
subject: Medicine
subject: Cell Biology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Cancer
subject: Plant Biology

description: Pomegranate peel extracts prepared in our laboratories from a waste of juice fruit processing were tested on bovine peripheral blood mononuclear cells to evaluate the effects on viability, oxidative stress and proliferation. The (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay pointed out that the extracts were not cytotoxic at the tested concentrations (0.1, 1.0, and 10 µg/mL). A moderate protective effect against Reactive Oxygen Species production induced by hydrogen peroxide or lipopolysaccharide and a significant anti-proliferative activity against proliferation induced by concanavalin A were observed on cell lines treated with the extracts at 10 μg/mL. Based on these results, pomegranate peel extracts seem promising as feed supplement for dairy cattle, in particular around calving, when the animals are subjected to an increase of the metabolic activity, responsible for oxidative stress and diseases. However, in vivo studies are needed to investigate the stability of the extracts across the bovine gastrointestinal tract barrier.
Novel bioactive compound from the bark of Putranjiva roxburghii Wall
Creators: name: Mishra, Sonali
name: Kumar, Saurabh
name: Darokar, Mahendra P.
name: Shanker, Karuna
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine

description: Putranjivah (Putranjiva roxburghii Wall, family – Putranjivaceae) is an Indian native medicinal plant used to treat many diseases such as treatment of mouth and stomach ulcers, hot swellings, smallpox, burning sensation and ophthalmopathy. The study of chemical constituents in the bark of P. roxburghii resulted in a new triterpene (6) along with five known triterpenoids (1–5). The chemical characterisation was based on 1H, 13C, 2D-NMR experimentation, and ESI-MS data. The anti-plasmodial activity was investigated by measuring parasite-specific lactate dehydrogenase (pLDH) based in vitro assay. The IC50 value results showed that friedlein (2.40 ± 0.70) and roxburghonol (4.10 ± 1.7 μg/ml) possess better anti-plasmodial activity than other isolated triterpenes (2–5) but not as potent as chloroquine (0.023 ± 0.002 μg/ml) against chloroquine-sensitive Plasmodium falciparum (3D7) strain.
Limb darkening in spherical stellar atmospheres
Creators: name: Neilson, Hilding R.
name: Lester, John B.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: (Abridged) Context. Stellar limb darkening, I(μ = cosθ), is an important constraint for microlensing, eclipsing binary, planetary transit, and interferometric observations, but is generally treated as a parameterized curve, such as a linear-plus-square-root law. Many analyses assume limb-darkening coefficients computed from model stellar atmospheres. However, previous studies, using I(μ) from plane- parallel models, have found that fits to the flux-normalized curves pass through a fixed point, a common μ location on the stellar disk, for all values of T eff, log g and wavelength. Aims. We study this fixed μ-point to determine if it is a property of the model stellar atmospheres or a property of the limb-darkening laws. Furthermore, we use this limb-darkening law as a tool to probe properties of stellar atmospheres for comparison to limb- darkening observations. Methods. Intensities computed with plane-parallel and spherically-symmetric Atlas models (characterized by the three fundamental parameters L\star, M\star and R\star) are used to reexamine the existence of the fixed μ-point for the parametrized curves. Results. We find that the intensities from our spherical models do not have a fixed point, although the curves do have a minimum spread at a μ-value similar to the parametrized curves. We also find that the parametrized curves have two fixed points, μ1 and μ2, although μ2 is so close to the edge of the disk that it is missed using plane-parallel atmospheres. We also find that the spherically- symmetric models appear to agree better with published microlensing observations relative to plane-parallel models.
description: 8 pages, 8 figures, figures 4 and 6 have lower resolution. A&A in press