cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Axisymmetric toroidal modes of general relativistic magnetized neutron star models
Creators: name: Asai, Hidetaka
name: Lee, Umin
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We calculate axisymmetric toroidal modes of magnetized neutron stars with a solid crust in the general relativistic Cowling approximation. We assume that the interior of the star is threaded by a poloidal magnetic field, which is continuous at the surface with an outside dipole field. We examine the cases of the field strength $B_{\rm{S}}\sim10^{16}$ G at the surface. Since separation of variables is not possible for the oscillations of magnetized stars, we employ finite series expansions for the perturbations using spherical harmonic functions. We find discrete normal toroidal modes of odd parity, but no toroidal modes of even parity are found. The frequencies of the toroidal modes form distinct mode sequences and the frequency in a given mode sequence gradually decreases as the number of radial nodes of the eigenfunction increases. From the frequency spectra computed for neutron stars of different masses, we find that the frequency is almost exactly proportional to $B_{\rm{S}}$ and is well represented by a linear function of $R/M$ for a given $B_{\rm{S}}$, where $M$ and $R$ are the mass and radius of the star. The toroidal mode frequencies for $B_{\rm{S}}\sim 10^{15}$ G are in the frequency range of the quasi-periodic oscillations (QPOs) detected in the soft-gamma-ray repeaters, but we find that the toroidal normal modes cannot explain all the detected QPO frequencies.
Nanoscale Metal−Organic Frameworks as Potential Multimodal Contrast Enhancing Agents
Creators: name: Taylor, Kathryn M. L.
name: Lin, Wenbin
name: An, Hongyu
name: Rieter, William J.
name: Lin, Weili
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Nanoscale metal-organic frameworks (NMOFs) based on Gd3+ centers and benzenedicarboxylate and benzenetricarboxylate bridging ligands were synthesized using reverse microemulsions and characterized using SEM, PXRD, and TGA. These NMOFs exhibit extraordinarily large R1 and R2 relaxivities because of the presence of up to tens of millions of Gd3+ centers in each nanoparticle and are thus efficient T1 and T2 contrast agents for MRI. The NMOFs can also be made highly luminescent by doping with Eu3+ or Tb3+ centers. The results from this work suggest that NMOFs can be used as potential contrast agents for multimodal imaging.
Quadratic algebra structure and spectrum of a new superintegrable system in N-dimension
Creators: name: Hoque, Md. Fazlul
name: Marquette, Ian
name: Zhang, Yao-Zhong
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We introduce a new superintegrable Kepler-Coulomb system with non-central terms in $N$-dimensional Euclidean space. We show this system is multiseparable and allows separation of variables in hyperspherical and hyperparabolic coordinates. We present the wave function in terms of special functions. We give a algebraic derivation of spectrum of the superintegrable system. We show how the $so(N+1)$ symmetry algebra of the $N$-dimensional Kepler-Coulomb system is deformed to a quadratic algebra with only 3 generators and structure constants involving a Casimir operator of $so(N-1)$ Lie algebra. We construct the quadratic algebra and the Casimir operator. We show this algebra can be realized in terms of deformed oscillator and obtain the structure function which yields the energy spectrum.
description: 21 pages
PHYSICOCHEMICAL PROPERTIES AND NUTRITIONAL VALUES OF REDUCED-SUGAR GALANGA JELLY FROM GALANGA ROOT EXTRACT
Creators: name: Pattama Supaphon
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Galanga
Jelly
Sucralose
Maltitol
Sweetener

description: Life Sciences and Environment Journal, 23, 1, 143-156
Symbiotic Reagent Activation:  Oppenauer Oxidation of Magnesium Alkoxides by Silylglyoxylates Triggers Second-Stage Aldolization
Creators: name: Satterfield, Andrew D.
name: Linghu, Xin
name: Johnson, Jeffrey S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: The treatment of silylglyoxylates with magnesium alkoxides at ambient temperature results in symbiotic Oppenauer oxidation of the alkoxide and Meerwein-Ponndorf-Verley reduction of the silylglyoxylate. The reduced silylglyoxylate undergoes subsequent [1,2]-Brook rearrangement and aldol reaction with the carbonyl oxidation product. The magnesium alkoxide may be accessed via deprotonation of primary or secondary alcohols with EtMgBr, via addition of Grignard reagents to aldehydes, or via CuI-catalyzed alkylation of epoxides. For aliphatic primary alkoxides, moderate levels of anti diastereoselection are observed. A crossover experiment reveals that dissociation of the nascent aldehyde from the magnesium center is faster than [1,2]-Brook rearrangement and aldolization.
Treating posttraumatic stress disorder at home in a single week using 1‐week virtual massed cognitive processing therapy
Creators: name: Held, Philip
name: Kovacevic, Merdijana
name: Petrey, Kelsey
name: Meade, Enya A
name: Pridgen, Sarah
name: Montes, Mauricio
name: Werner, Brianna
name: Miller, Michelle L
name: Smith, Dale L
name: Kaysen, Debra
name: Karnik, Niranjan S
Publisher: name: University of Illinois at Chicago
Year: 2022
Subjects: Uncategorized

description: Posttraumatic stress disorder (PTSD) treatments are increasingly delivered in massed formats and have shown comparable results to standard, weekly treatment. To date, massed cognitive processing therapy (CPT), delivered daily, has been delivered primarily in combination with adjunctive services and among veteran populations, but it has not been rigorously evaluated as a standalone intervention. The present study evaluated 1-week massed CPT delivered virtually (i.e., via telehealth) to a community sample of trauma-exposed individuals (N = 24). Using a single-arm open-label design, participants received CPT twice per day for 5 days. The results indicated that most participants completed treatment (n = 23, 95.8%), and no adverse events were reported. Participants exhibited large reductions in clinician-rated, d = 2.01, and self-reported PTSD symptoms, d = 2.55, as well as self-reported depressive symptoms, d = 1.46. On average, participants reported a 5-point PTSD symptom reduction and 1-point reduction in depressive symptoms for each treatment day. Reductions in PTSD and depressive symptoms were maintained at 3-month follow-up. Overall, 1-week massed CPT delivered virtually was shown to be feasible and to result in rapid symptom reductions that were sustained over time. Virtual massed CPT has the potential to increase access to effective treatments and help trauma survivors restore aspects of their lives in short amounts of time.
A STUDY OF POTENTIAL FLOOD RETENTION AREAS FOR STORING WATER USE IN THE DRY PERIOD IN UPPER CHI RIVER BASIN
Creators: name: Duangnapa Vanichsan
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Flood retention area
Water use in dry season
Upper Chi River Basin

description: Life Sciences and Environment Journal, 23, 1, 157-169
Object-Oriented Programming, Functional Programming and R
Creators: name: Chambers, John M.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Methodology (stat.ME)
subject: Programming Languages (cs.PL)
subject: Software Engineering (cs.SE)
subject: Computation (stat.CO)
subject: FOS: Computer and information sciences

description: This paper reviews some programming techniques in R that have proved useful, particularly for substantial projects. These include several versions of object-oriented programming, used in a large number of R packages. The review tries to clarify the origins and ideas behind the various versions, each of which is valuable in the appropriate context. R has also been strongly influenced by the ideas of functional programming and, in particular, by the desire to combine functional with object oriented programming. To clarify how this particular mix of ideas has turned out in the current R language and supporting software, the paper will first review the basic ideas behind object-oriented and functional programming, and then examine the evolution of R with these ideas providing context. Functional programming supports well-defined, defensible software giving reproducible results. Object-oriented programming is the mechanism par excellence for managing complexity while keeping things simple for the user. The two paradigms have been valuable in supporting major software for fitting models to data and numerous other statistical applications. The paradigms have been adopted, and adapted, distinctively in R. Functional programming motivates much of R but R does not enforce the paradigm. Object-oriented programming from a functional perspective differs from that used in non-functional languages, a distinction that needs to be emphasized to avoid confusion. R initially replicated the S language from Bell Labs, which in turn was strongly influenced by earlier program libraries. At each stage, new ideas have been added, but the previous software continues to show its influence in the design as well. Outlining the evolution will further clarify why we currently have this somewhat unusual combination of ideas.
description: Published in at http://dx.doi.org/10.1214/13-STS452 the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Temperature- and Solvent-Dependent Binding of Dihydrogen in Iridium Pincer Complexes
Creators: name: Heinekey, D. Michael
name: Brookhart, Maurice
name: Göttker-Schnetmann, Inigo
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Mixtures of deuterium labeled complexes (p-XPOCOP)IrH2–xDx (1–6-d0–2) {POCOP = [C6H2-1,3-[OP(tBu)2]2; X = MeO (1), Me (2), H (3), F (4), C6F5 (5), and ArF = 3,5-(CF3)2-C6H3 (6)} have been generated by reaction of (p-XPOCOP)IrH2 complexes with HD gas in benzene followed by removal of the solvent under high vacuum. Spectroscopic analysis employing 1H and 2D NMR reveals significant temperature and solvent dependent isotopic shifts and HD coupling constants. Complexes 1–6-d1 in toluene and pentane between 296 K and 213 K exhibit coupling constants JHD of 3.8–9.0 Hz, suggesting the presence of an elongated H2 ligand, which is confirmed by T1(min) measurements of complexes 1, 3 and 6 in toluene-d8. In contrast, complex 6-d1 exhibits JHD = 0 Hz in CH2Cl2 or CDCl2F while isotopic shifts up to −4.05 ppm have been observed by lowering the temperature from 233 K to 133 K in CDCl2F. The large and temperature dependent isotope effects are attributed to non-statistical occupation of two different hydride environments. The experimental observations are interpreted in terms of a two component model involving rapid equilibration of solvated Ir(III) dihydride and Ir(I) dihydrogen structures.
Role of dimensionality in spontaneous magnon decay: easy-plane ferromagnet
Creators: name: Stephanovich, V. A.
name: Zhitomirsky, M. E.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We calculate magnon lifetime in an easy-plane ferromagnet on a tetragonal lattice in transverse magnetic field. At zero temperature magnons are unstable with respect to spontaneous decay into two other magnons. Varying ratio of intrachain to interchain exchanges in this model we consider the effect of dimensionality on spontaneous magnon decay. The strongest magnon damping is found in the quasi-one-dimensional case for momenta near the Brillouin zone boundary. The sign of a weak interchain coupling has a little effect on the magnon decay rate. The obtained theoretical results suggest possibility of experimental observation of spontaneous magnon decay in a quasi-one-dimensional ferromagnet CsNiF$_3$. We also find an interesting enhancement of the magnon decay rate for a three-dimensional ferromagnet. The effect is present only for the nearest-neighbor model and is related to effective dimensionality reduction in the two-magnon continuum.
description: 6 pages, 6 figures
Activation of sp 3 C−H Bonds with Cobalt(I):  Catalytic Synthesis of Enamines
Creators: name: Bolig, Andrew D.
name: Brookhart, Maurice
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: C-H bond activation has been extensively studied with (Cp*)M(L)n (M = Ir, Rh), but cobalt, the third member of this triad, has not previously been shown to activate sp3 C-H bonds. Further, practical functionalization of the metal alkyl products of oxidative addition has not been fully explored. Toward these ends, we have developed catalytic dehydrogenation of alkyl amines with a Co(I) catalyst. Amine substrates are protected with vinyl silanes, followed by catalytic transfer hydrogenation, to yield a broad range of stable protected enamines and 1,2-diheteroatom-substituted alkenes, including several unprecedented heterocycles. (Cp*)Co(VTMS)2 catalyzes transfer hydrogenation under surprisingly mild conditions with high chemo-, regio-, and diastereoselectivity, while tolerating additional functionality.
Fluid Inclusion Research: Proceedings of COFFI. Volume 17, 1984.
Creators: Roedder, Edwin, editor
Kozlowski, Andrzej, associate editor
Publisher: name: University of Alberta Library
Year: 1984

A yearly volume to provide communication between workers in various fields of research on fluid inclusions, using the term in its broadest sense to embrace inclusions of any fluid, gas, liquid, or melt, and in any natural material, terrestrial or extraterrestrial.
DESIGN AND CONSTRUCT OF THE SAJOR-CAJU MUSHROOM SHREDDING MACHINE PROTOTYPE
Creators: name: Thawanrat Sumrit
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Shredding machine
Sajor-caju mushroom
Efficiency
Reduce time

description: Life Sciences and Environment Journal, 23, 1, 170-183
Enantioselective Metallophosphite-Catalyzed C-Acylation of Nitrones
Creators: name: Garrett, Mary R.
name: Tarr, James C.
name: Johnson, Jeffrey S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Metallophosphites derived from tartaric acid catalyze the enantioselective addition of acyl silanes to nitrones. The product alpha N-silyloxyamino ketones are obtained in moderate to good yields (36-94%) with excellent enantioselectivity (er >= 95:5). The nitrone oxygen is essential in facilitating the silyl transfer that is required for catalyst turnover. This represents, to the best of our knowledge, the first example of C-acylation of nitrones and the most highly enantioselective catalytic addition of an acyl anion equivalent to an azomethine electrophile. The N-O bond of the product may be reductively cleaved under mild conditions to provide N- aryl alpha-amino ketones with negligible loss of enantiopurity.
Class I Methanol (CH$_{3}$OH) Maser Conditions near Supernova Remnants
Creators: name: McEwen, Bridget C.
name: Pihlström, Ylva M.
name: Sjouwerman, Loránt O.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present results from calculations of the physical conditions necessary for the occurrence of 36.169 ($4_{-1}-3_{0}\, E$), 44.070 ($7_{0}-6_{1}\,A^+$), 84.521 ($5_{-1}-4_{0}\,E$), and 95.169 ($8_{0}-7_{1}\,A^+$) GHz methanol (CH$_3$OH) maser emission lines near supernova remnants (SNRs), using the MOLPOP-CEP program. The calculations show that given a sufficient methanol abundance, methanol maser emission arises over a wide range of densities and temperatures, with optimal conditions at $n\sim 10^4-10^6$ cm$^{-3}$ and $T>60$ K. The 36~GHz and 44~GHz transitions display more significant maser optical depths compared to the 84~GHz and 95~GHz transitions over the majority of physical conditions. It is also shown that line ratios are an important and applicable probe of the gas conditions. The line ratio changes are largely a result of the $E$-type transitions becoming quenched faster at increasing densities. The modeling results are discussed using recent observations of CH$_3$OH and hydroxyl (OH) masers near the supernova remnants G1.4$-$0.1, W28, and Sgr A East.
Conflating point of interest (POI) data: A systematic review of matching methods
Creators: name: Sun, Kai
name: Hu, Yingjie
name: Ma, Yue
name: Zhou, Ryan Zhenqi
name: Zhu, Yunqiang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: Point of interest (POI) data provide digital representations of places in the real world, and have been increasingly used to understand human-place interactions, support urban management, and build smart cities. Many POI datasets have been developed, which often have different geographic coverages, attribute focuses, and data quality. From time to time, researchers may need to conflate two or more POI datasets in order to build a better representation of the places in the study areas. While various POI conflation methods have been developed, there lacks a systematic review, and consequently, it is difficult for researchers new to POI conflation to quickly grasp and use these existing methods. This paper fills such a gap. Following the protocol of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we conduct a systematic review by searching through three bibliographic databases using reproducible syntax to identify related studies. We then focus on a main step of POI conflation, i.e., POI matching, and systematically summarize and categorize the identified methods. Current limitations and future opportunities are discussed afterwards. We hope that this review can provide some guidance for researchers interested in conflating POI datasets for their research.
Self-Assembled Hybrid Nanoparticles for Cancer-Specific Multimodal Imaging
Creators: name: Lin, Weili
name: Rieter, William J.
name: Kim, Jason S.
name: Taylor, Kathryn M. L.
name: Lin, Wenbin
name: An, Hongyu
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: A layer-by-layer (LbL) polyelectrolyte deposition strategy is used to prepare multifunctional nanoparticles (MFNPs) with multimodal imaging capabilities. Alternating treatment of hybrid silica nanoparticles (NP0) containing a luminescent [Ru(bpy)3]Cl2 core and anionic monolayer coating of the Gd−(siloxylpropyl)diethylenetriamine tetraacetate (Gd−DTTA) complex with cationic Gd(III)−DOTA oligomer 1 and anionic poly(styrene sulfonate) (PSS) led to the deposition of multilayers of 1 and PSS via electrostatic interactions. This LbL deposition technique offers a superb strategy for the assembly of hybrid nanoparticles with imbedded luminophores and very high MR relaxivities. The PSS-terminated multilayered nanoparticles can be noncovalently functionalized with targeting peptides that carry positive charges under physiological conditions via electrostatic interactions to lead to cancer-specific MFNPs for optical and MR imaging of HT-29 human colon cancer cells. The generality of this approach should allow the de...
Static Enforcement of Role-Based Access Control
Creators: name: Ali, Asad
name: Fernández, Maribel
Publisher: name: arXiv
Year: 2014
Subjects: subject: Software Engineering (cs.SE)
subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences

description: We propose a new static approach to Role-Based Access Control (RBAC) policy enforcement. The static approach we advocate includes a new design methodology, for applications involving RBAC, which integrates the security requirements into the system's architecture. We apply this new approach to policies restricting calls to methods in Java applications. We present a language to express RBAC policies on calls to methods in Java, a set of design patterns which Java programs must adhere to for the policy to be enforced statically, and a description of the checks made by our static verifier for static enforcement.
description: In Proceedings WWV 2014, arXiv:1409.2294
Surface Modification and Functionalization of Nanoscale Metal-Organic Frameworks for Controlled Release and Luminescence Sensing
Creators: name: Taylor, Kathryn M. L.
name: Lin, Wenbin
name: Rieter, William J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: We describe in this paper a general method for synthesizing a new class of nanocomposites with a nanoscale metal-organic framework (NMOF) core and a silica shell. Silica shells of variable thickness were deposited on the NMOFs that had been surface-modified with polyvinylpyrrolidone (PVP) using a sol-gel procedure. The NMOF core of the nanocomposite could be completely removed (via dissolution) at low pH to afford hollow silica shells with varied thickness and aspect ratios. We also showed that the silica shell of such nanocomposites significantly stabilized the NMOF core against dissolution, thus demonstrating the ability to control the release of metal constituents from such silica-coated NMOFs. The silica shell was further functionalized with a silylated Tb-EDTA monoamide derivative for the luminescence sensing of dipicolinic acid (DPA), which is a major constituent of many pathogenic spore-forming bacteria. Owing to the tunability of NMOF composition and morphology, the present approach should allow for the synthesis of not only interesting nanoshells that are not accessible with presently available templates but also novel core-shell hybrid nanostructures for future imaging, sensing, and drug delivery applications.
EFFECT OF FERMENTED WATER HYACINTH AND RESIDUAL WASTE ON GERMINATION AND GROWTH OF GREEN OAK LETTUCE
Creators: name: Chakkrit Sreela-Or
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Water hyacinth
Residual waste
Green oak lettuce

description: Life Sciences and Environment Journal, 23, 1, 196-207
Neutrino Emission in Jet Propagation Process
Creators: name: Xiao, D.
name: Dai, Z. G.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Relativistic jets are universal in long-duration gamma-ray burst (GRB) models. Before breaking out, they must propagate in the progenitor envelope along with a forward shock and a reverse shock forming at the jet head. Both electrons and protons will be accelerated by the shocks. High energy neutrinos could be produced by these protons interacting with stellar materials and electron-radiating photons. The jet will probably be collimated, which may have a strong effect on the final neutrino flux. Under the assumption of a power-law stellar-envelope density profile $ρ\propto r^{-α}$ with an index $α$, we calculate this neutrino emission flux by these shocks for low-luminosity GRBs (LL-GRBs) and ultra-long GRBs (UL-GRBs) in different collimation regimes, using the jet propagation framework developed by \citet{bro11}. We find that LL-GRBs and UL-GRBs are capable for detectable high energy neutrinos up to $\sim {\rm PeV}$, and obtain the final neutrino spectrum. Besides, we conclude that larger $α$ corresponds to greater neutrino flux at high energy end ($\sim {\rm PeV}$) and higher maximum neutrino energy as well. However, such differences are so small that it is not promising for us to distinguish from observations, given the energy resolution we have now.
description: 21 pages, 4 figures, accepted for publication in ApJ
UPGRADING WASTE FROM CROCODILE MIXED BAMBOO BAMBOO SAWDUST PELLET
Creators: name: Chanon Bunmephiphit
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Crocodile manure
Bamboo sawdust
Biomass
Pellet

description: Life Sciences and Environment Journal, 23, 1, 208-218
THE EVALUATION OF DRILLING PERFORMANCE OF NAM PHI DRILL BIT
Creators: name: Adul Phuk-In
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Property enhancement of Nam Phi Iron
Drill bit cutting machine creation
Re-vulcanization
Induction cooker

description: Life Sciences and Environment Journal, 23, 1, 219-234
Carbohydrate−π Interactions: What Are They Worth?
Creators: name: Riemen, Alex J.
name: Waters, Marcey L.
name: Laughrey, Zachary R.
name: Kiehna, Sarah E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Protein-carbohydrate interactions play an important role in many biologically important processes. The recognition is mediated by a number of noncovalent interactions including an interaction between the α-face of the carbohydrate and the aromatic side chain. To this end, this interaction has been studied in the context of a β-hairpin in aqueous solution, in which the interaction can be investigated in the absence of other cooperative noncovalent interactions. In this β-hairpin system both the aromatic side chain as well as the carbohydrate was varied in an effort to gain greater insight into the driving force and magnitude of the carbohydrate-π interaction. The magnitude of the interaction was found to vary from -0.5 to -0.8 kcal/mol, depending on the nature of the aromatic ring and the carbohydrate. Replacement of the aromatic ring with an aliphatic group resulted in a decrease in interaction energy to -0.1 kcal/mol, providing evidence for the contribution of CH-π interactions to the driving force. These findings demonstrate the significance of carbohydrate-π interactions within biological systems and also demonstrate its utility as a molecular recognition element in designed systems
The Adaptive Optics System for the Gemini Infrared Multi-Object Spectrograph: Performance Modeling
Creators: name: Conod, Uriel
name: Jackson, Kate
name: Turri, Paolo
name: Chapman, Scott
name: Lardière, Olivier
name: Lamb, Masen
name: Correia, Carlos
name: Sivo, Gaetano
name: Sivanandam, Suresh
name: Véran, Jean-Pierre
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The Gemini Infrared Multi-Object Spectrograph (GIRMOS) will be a near-infrared, multi-object, medium spectral resolution, integral field spectrograph (IFS) for Gemini North Telescope, designed to operate behind the future Gemini North Adaptive Optics system (GNAO). In addition to a first ground layer Adaptive Optics (AO) correction in closed loop carried out by GNAO, each of the four GIRMOS IFSs will independently perform additional multi-object AO correction in open loop, resulting in an improved image quality that is critical to achieve top level science requirements. We present the baseline parameters and simulated performance of GIRMOS obtained by modeling both the GNAO and GIRMOS AO systems. The image quality requirement for GIRMOS is that 57% of the energy of an unresolved point-spread function ensquared within a 0.1 x 0.1 arcsecond at 2.0 μ m. It was established that GIRMOS will be an order 16 x 16 adaptive optics (AO) system after examining the tradeoffs between performance, risks and costs. The ensquared energy requirement will be met in median atmospheric conditions at Maunakea at 30° from zenith.
description: 13 pages, 10 figures, Publications of the Astronomical Society of the Pacific
Differential Dynamical Effects of Macromolecular Crowding on an Intrinsically Disordered Protein and a Globular Protein: Implications for In-Cell NMR Spectroscopy
Creators: name: Charlton, Lisa M.
name: Pielak, Gary J.
name: Wang, Guifang
name: Young, Gregory B.
name: Macdonald, Jeffrey M.
name: Lakkavaram, Asha
name: Li, Conggang
name: Seagle, Christopher
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: In-cell NMR provides a valuable means to assess how macromolecules, with concentrations up to 300 g/L in the cytoplasm, affect the structure and dynamics of proteins at atomic resolution. Here an intrinsically disordered protein, alpha-synuclein (alphaSN), and a globular protein, chymotrypsin inhibitor 2 (CI2) were examined by using in-cell NMR. High-resolution in-cell spectra of alphaSN can be obtained, but CI2 leaks from the cell and the remaining intracellular CI2 is not detectable. Even after stabilizing the cells from leakage by using alginate encapsulation, no CI2 signal is detected. From in vitro studies we conclude that this difference in detectability is the result of the differential dynamical response of disordered and ordered proteins to the changes of motion caused by the increased viscosity in cells.
Suppression of work fluctuations by optimal control: An approach based on Jarzynski's equality
Creators: name: Xiao, Gaoyang
name: Gong, Jiangbin
Publisher: name: arXiv
Year: 2014
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Understanding and manipulating work fluctuations in microscale and nanoscale systems are of both fundamental and practical interest. For example, aspects of work fluctuations will be an important factor in designing nanoscale heat engines. In this work, an optimal control approach directly exploiting Jarzynski's equality is proposed to effectively suppress the fluctuations in the work statistics, for systems (initially at thermal equilibrium) subject to a work protocol but isolated from a bath during the protocol. The control strategy is to minimize the deviations of individual values of exp(-βW) from their ensemble average given by exp(-βΔF}, where W is the work, β is the inverse temperature, and ΔF is the free energy difference between two equilibrium states. It is further shown that even when the system Hamiltonian is not fully known, it is still possible to suppress work fluctuations through a feedback loop, by refining the control target function on the fly through Jarzynski's equality itself. Numerical experiments are based on linear and nonlinear parametric oscillators. Optimal control results for linear parametric oscillators are also benchmarked with early results based on accelerated adiabatic processes.
description: 12 pages, 8 figures, 3 tables. Comments are most welcome
Synergies in extragalactic and Galactic jet research
Creators: name: Romero, Gustavo E.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The discovery of relativistic jets and superluminal sources associated with accreting X-ray binaries in the Galaxy opened new ways of investigating the physics of outflows from compact objects. The short timescales and relatively large angular sizes of Galactic jets allow to probe the physics of relativistic outflows to unprecedented details. In this article I discuss results of recent modelling of Galactic jets, covering both radiative and dynamical aspects, which can shed light on different features of their extragalactic cousins.
description: 9 pages, 7 figures. To appear in the Proceedings of the IAU Symposium No. 313: "Extragalactic jets from every angle", Galapagos, Ecuador, 15-19 September 2014, F. Massaro, C. C. Cheung, E. Lopez, and A. Siemiginowska (Eds.), Cambridge University Press
Spontaneous and parametric processes in warm rubidium vapours
Creators: name: Dąbrowski, Michał
name: Parniak, Michał
name: Pęcak, Daniel
name: Chrapkiewicz, Radosław
name: Wasilewski, Wojciech
Publisher: name: arXiv
Year: 2014
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Warm rubidium vapours are known to be a versatile medium for a variety of experiments in atomic physics and quantum optics. Here we present experimental results on producing the frequency converted light for quantum applications based on spontaneous and stimulated processes in rubidium vapours. In particular, we study the efficiency of spontaneously initiated stimulated Raman scattering in the Λ-level configuration and conditions of generating the coherent blue light assisted by multi-photon transitions in the diamond-level configuration. Our results will be helpful in search for new types of interfaces between light and atomic quantum memories.
description: 14 pages, 6 figures, accepted for publication in Latvian Journal of Physics and Technical Sciences
Distinct Reactivity of Pd(OTs) 2 : The Intermolecular Pd(II)-Catalyzed 1,2-Carboamination of Dienes
Creators: name: Bailey, Chris D.
name: Gagné, Michel R.
name: Booker-Milburn, Kevin I.
name: Houlden, Chris E.
name: Ford, J. Gair
name: Lloyd-Jones, Guy C.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: A Pd-catalyzed intermolecular 1,2-carboamination route to indolines from N-aryl ureas and 1,3-dienes that proceeds under mild conditions in relatively nonacidic media, is presented. The in situ generation, or preformation, of a palladium tosylate emerges as a key parameter in gaining the requisite reactivity for the C-H insertion/carbopalladation/nucleophilic displacement process.
RELATIONSHIP OF AQUATIC ENVIRONMENTAL PARAMETERS AND PHYTOPLANKTON DENSITY IN PARKMENG ESTUARY, SIKAO DISTRICT, TRANG PROVINCE
Creators: name: Patchara Pedprada
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Phytoplankton
Aquatic parameter
Relationship
Estuary
Andaman Sea

description: Life Sciences and Environment Journal, 23, 2, 271-282
Inhibition of HIV Fusion with Multivalent Gold Nanoparticles
Creators: name: Ballard, T. Eric
name: Melander, Christian
name: Bowman, Mary-Catherine
name: Margolis, David M.
name: Feldheim, Daniel L.
name: Ackerson, Christopher J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: The design and synthesis of a multivalent gold nanoparticle therapeutic is presented. SDC-1721, a fragment of the potent HIV inhibitor TAK-779, was synthesized and conjugated to 2.0 nm diameter gold nanoparticles. Free SDC-1721 had no inhibitory effect on HIV infection; however, the (SDC-1721)-gold nanoparticle conjugates displayed activity comparable to that of TAK-779. This result suggests that multivalent presentation of small molecules on gold nanoparticle surfaces can convert inactive drugs into potent therapeutics.
Light-Mediated Liberation of Enzymatic Activity: “Small Molecule” Caged Protein Equivalents
Creators: name: Lawrence, David S.
name: Li, Haishan
name: Hah, Jung-Mi
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Light-activatable (“caged”) proteins have been used to correlate, with exquisite temporal and spatial control, intracellular biochemical action with global cellular behavior. However, the chemical or genetic construction of caged proteins is nontrivial, with subsequent laborious introduction into living cells, potentially problematic competition with natural endogenous counterparts, and challenging intracellular incorporation at levels equivalent to the natural enzymes. We describe the design, synthesis, and characterization of small molecular equivalents of a caged Src kinase. These compounds are easy to prepare and function by inhibiting the action of the natural unmodified enzyme.
Entangled Orbital Triplet Pairs in Iron-Based Superconductors
Creators: name: Ong, T. Tzen
name: Coleman, P.
name: Schmalian, J.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A key question in high temperature iron-based superconductivity is the mechanism by which the paired electrons minimize their strong mutual Coulomb repulsion. While electronically paired superconductors generally avoid the Coulomb interaction through the formation of nodal, higher angular momentum pairs, iron based superconductors appear to form singlet s-wave (s$^{\pm}$) pairs. By taking the orbital degrees of freedom of the iron atoms into account, here we argue that the s$^{\pm}$ state in these materials possesses internal d-wave structure, in which a relative d-wave ($L=2$) motion of the pairs entangles with the ($I=2$) internal angular momenta of the d-orbitals to form a low spin $J=L+I=0$ singlet. We discuss how the recent observation of a nodal gap with octahedral structure in KFe$_{2}$As$_{2}$ can be understood as a high spin ($J=L+I=4$) configuration of the orbital and isospin angular momenta; the observed pressure-induced phase transition into a fully gapped state can then interpreted as a high-to-low spin phase transition of the Cooper pairs.
description: An online supplementary material has been included
Mg 2+ -Free Bacillus stearothermophilus Tryptophanyl-tRNA Synthetase Retains a Major Fraction of the Overall Rate Enhancement for Tryptophan Activation
Creators: name: Weinreb, Violetta
name: Carter, Charles W.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Few experimental data are available for rates of enzymatic phosphoryl-transfer reactions in the absence of the divalent metal ions associated with such reactions. Such data are of interest for amino acid activation by class Ic aminoacyl-tRNA synthetases, for which there is substantial evidence that binding energy of ATP may account for a major fraction of the overall rate enhancement, and it is crucial to know if these effects themselves depend on the divalent metal ion. We describe a nested, non-linear model for the sum of metal-free and metal-catalyzed activities and its use in determining metal-free enzyme activity jointly with transition-state metal binding affinity, by fitting observed values obtained from Mg2+-depleted assays with increasing [EDTA] at known [Mg2+]total. Tryptophan activation by B. stearothermophilus tryptophanyl-tRNA synthetase falls asymptotically to a plateau value five orders of magnitude below that observed for the Mg2+-supplemented enzyme at EDTA concentrations that reduce the free metal concentration to <1 pmolar. The fitted regression model parameters yield a relative rate acceleration of 9.3 × 104 attributable to the catalytic effect of Mg2+ and an enhanced (KE‡ = 1.15 × 10−7 M) transition-state binding of Mg2+. Factorial analysis indicates that 80% of the reduction in free energy of activation effected by TrpRS arises from protein-ligand interactions.
OPTIMUM CONDITIONS OF USING BIO-EXTRACT FROM URINE WITH VINASSE AND MANURE AFFECTING YIELDS OF MARIGOLD
Creators: name: Chakkrit Sreela-Or
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Optimization
Bio-extract
Marigold

description: Life Sciences and Environment Journal, 23, , 283-296
Metastability and dynamic modes in magnetic island chains
Creators: name: Wysin, G. M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The uniform states of a model for one-dimensional chains of thin magnetic islands on a nonmagnetic substrate coupled via dipolar interactions are described here. Magnetic islands oriented with their long axes perpendicular to the chain direction are assumed, whose shape anisotropy imposes a preference for the dipoles to point perpendicular to the chain. The competition between anisotropy and dipolar interactions leads to three types of uniform states of distinctly different symmetries, including metastable transverse or remanent states, transverse antiferromagnetic states, and longitudinal states where all dipoles align with the chain direction. The stability limits and normal modes of oscillation are found for all three types of states, even including infinite range dipole interactions. The normal mode frequencies are shown to be determined from the eigenvalues of the stability problem.
Rates of Spontaneous Cleavage of Glucose, Fructose, Sucrose, and Trehalose in Water, and the Catalytic Proficiencies of Invertase and Trehalas
Creators: name: Wolfenden, Richard
name: Yuan, Yang
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: The half-lives for spontaneous hydrolysis of trehalose and sucrose at 25 °C are 6.6 × 106 years and 440 years. The half-lives for decomposition of the hydrolysis products glucose and fructose are 96 years and 70 days, respectively. Whereas sucrose and trehalose differ by a factor of 15000 in their rates of uncatalyzed hydrolysis, the reactions catalyzed by invertase (EC 3.2.1.26) and trehalase (EC 3.2.1.28) proceed at similar rates. Accordingly, the attainments of invertase as a catalyst are modest, but the rate enhancement and catalytic proficiency produced by trehalase approach the high levels achieved by polysaccharide hydrolases.
Residue-Level Interrogation of Macromolecular Crowding Effects on Protein Stability
Creators: name: Orans, Jillian
name: Charlton, Lisa M.
name: Barnes, Christopher O.
name: Young, Gregory B.
name: Pielak, Gary J.
name: Li, Conggang
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Theory predicts that macromolecular crowding affects protein behavior, but experimental confirmation is scant. Herein, we report the first residue-level interrogation of the effects of macromolecular crowding on protein stability. We observe up to a 100-fold increase in the stability, as measured by the equilibrium constant for folding, for the globular protein chymotrypsin inhibitor 2 (CI2) in concentrations of the cosolute poly(vinylpyrrolidone) (PVP) that mimic the protein concentration in cells. We show that the increased stability is caused by the polymeric nature of PVP and that the degree of stabilization depends on both the location of the individual residue in the protein structure and the PVP concentration. Our data reinforce the assertion that macromolecular crowding stabilizes the protein by destabilizing its unfolded states.
Reversibility Effects on the Stereoselectivity of Pt(II)-Mediated Cascade Poly-ene Cyclizations
Creators: name: Feducia, Jeremiah A.
name: Gagné, Michel R.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Cyclization of 1,5-dienes bearing nucleophilic traps with electrophilic trisphosphine pincer ligated Pt(II) complexes results in the formation of a polycyclic Pt-alkyl via an Pt(η2-alkene) intermediate. With electron rich triphosphine ligands an equilibrium between the Pt(η2-alkene) and Pt-alkyl was observed. The position of the equilibrium was sensitive to ligand basicity, conjugate acid strength, solvent polarity, and ring size. In cases where the ligand was electron poor and did not promote retro-cyclization, then kinetic products adhering to the Stork-Eschenmoser postulate were observed (E-alkenes give trans-ring junctions). When retrocyclization was rapid, then alternative thermodynamic products resulting from multi-step rearrangements were observed (cis [6,5]-bicycles). Under both kinetic and thermodynamic conditions remote methyl substituents led to highly diastereoselective reactions. In the case of trienol substrates, long-range asymmetric induction from a C-ring substituent was considerably attenuated and only modest diastereoselectivity was observed (~2:1). The data suggests that for a tricyclization, the long-range stereocontrol results from diastereo-selecting interactions that develop during the organization of the nascent rings. In contrast, the bicyclization diastereoselectivities result from reversible cascade cyclization.
Discovery of Substructure in the Scatter-Broadened Image of Sgr A*
Creators: name: Gwinn, C. R.
name: Kovalev, Y. Y.
name: Johnson, M. D.
name: Soglasnov, V. A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We have detected substructure within the smooth scattering disk of the celebrated Galactic Center radio source Sagittarius A* (SgrA*). We observed this structure at 1.3 cm wavelength with the Very Long Baseline Array together with the Green Bank Telescope, on baselines of up to 3000 km, long enough to completely resolve the average scattering disk. Such structure is predicted theoretically, as a consequence of refraction by large-scale plasma fluctuations in the interstellar medium. Along with the much-studied $θ_\mathrm{d}\propto λ^2$ scaling of angular broadening $θ_\mathrm{d}$ with observing wavelength $λ$, our observations indicate that the spectrum of interstellar turbulence is shallow, with an inner scale larger than 300 km. The substructure is consistent with an intrinsic size of about 1 mas at 1.3 cm wavelength, as inferred from deconvolution of the average scattering. Further observations of the substructure can set stronger constraints on the properties of scattering material and on the intrinsic size of SgrA*. These constraints will guide understanding of effects of scatter-broadening and emission physics of the black hole, in images with the Event Horizon Telescope at millimeter wavelengths.
description: 5 pages, 5 figures, accepted by Astrophysical Journal Letters; minor corrections to the text and figures are introduced
EFFECTS OF CASSAVA BASED INTERCROPS WITH THAI-MELON ON WEED CONTROL AND LAND USE EFFICIENCY
Creators: name: Wimonsiri Sehawong
Publisher: name: Pibulsongkram Rajabhat University
Year: 2022
Subjects: Growth and yield
Cassava
Thai-melon
Mono crop
Intercrop

description: Life Sciences and Environment Journal, 23, 2, 297-305
Possible Half Metallic Antiferromagnetism in a Double Perovskite Material with Strong Spin-Orbit Couplings
Creators: name: Ghimire, Madhav P.
name: Wu, Long-Hua
name: Hu, Xiao
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Using the first-principles density functional approach, we investigate a material Pr$_2$MgIrO$_6$ (PMIO) of double perovskite structure synthesized recently. According to the calculations, PMIO is a magnetic Mott-Hubbard insulator influenced by the cooperative effect of spin-orbit coupling (SOC) and Coulomb interactions of Ir-5$d$ and Pr-4$f$ electrons, as well as the crystal field. When Pr is replaced with Sr gradually, the system exhibits half metallic (HM) states desirable for spintronics applications. In [Pr$_{2-x}$Sr$_x$MgIrO$_6$]$_2$, HM antiferromagnetism (HMAFM) with zero spin magnetization in the unit cell is obtained for $x=1$, whereas for $x=0.5$ and 1.5 HM ferrimagnetism (HMFiM) is observed with $μ_{\rm tot}=3μ_{\rm B}$ and $μ_{\rm tot}=-3μ_{\rm B}$ per unit cell respectively. It is emphasized that the large exchange splitting between spin-up and spin-down bands at the Fermi level makes the half metallicity possible even with strong SOC.
description: 8 pages, 7 figures