cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Crystals and affine Hecke algebras of type D
Creators: name: Kashiwara, Masaki
name: Miemietz, Vanessa
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Algebra (math.QA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 17B37, 20C08

description: The Lascoux-Leclerc-Thibon-Ariki theory asserts that the K-group of the representations of the affine Hecke algebras of type A is isomorphic to the algebra of functions on the maximal unipotent subgroup of the group associated with a Lie algebra $g$ where $g$ is $gl_\infty$ or the affine Lie algebra $A^{(1)}_\ell$, and the irreducible representations correspond to the upper global bases. Recently, N. Enomoto and the first author presented the notion of symmetric crystals and formulated analogous conjectures for the affine Hecke algebras of type B. In this note, we present similar conjectures for certain classes of irreducible representations of affine Hecke algebras of type D. The crystal for type D is a double cover of the one for type B.
description: 8 pages
Interactive effects of rice bran compost and chemical fertilizers on macronutrients, oil and protein content in sunflower (Helianthus annuus L.)
Creators: name: Alauddin, M.
name: Mohison, G.M.
name: Ali, A.H.M.Z.
name: Rahman, M.K.
name: Alauddin, M.
name: Mohison, G.M.
name: Ali, A.H.M.Z.
name: Rahman, M.K.
Publisher: name: Unknown
Year: 2020
Subjects: subject: Crop Production/Industries
subject: Oil and protein
subject: Rice bran and chemical fertilizers
subject: Sunflower
subject: Uptake

description: A field experiment was conducted at the research farm of Charfasson Govt. College, Bhola, Bangladesh in rabi season in 2015-2016 to evaluate the impact of conjunctive use of chemical fertilizers with rice bran on concentration, uptake and seed quality of sunflower cv. BARI-2 (Keroni-2). The experiment was laid out in the randomized complete block design (RCBD) having sixteen treatments with three replications. The size of the plots were 3 m x 2 m. Treatments were T1 Control (- RB and -NPK), T2: 2.5 t RB ha-1 , T3: 5.0 t RB ha-1 ,T4: 7.5 t RB ha-1 , T5: N40P30K50 kg ha-1 ,T6: N80P60K100 kg ha-1 , T7: N120P90K150 kg ha-1 , T8: 2.5 t RB ha-1 + N40P30K50 kg ha-1 , T9: 2.5 t RB ha-1 + N80P60K100 kg ha-1 , T10: 2.5 t RB ha-1 + N120P90K150 kg ha1 , T11: 5.0 t RB ha-1 + N40P30K50 kg ha-1 , T12: 5.0 t RB ha-1 + N80P60K100 kg ha-1 , T13: 5.0 t RB ha1 + N120P90K150 kg ha-1 , T14: 7.5 t RB ha-1 + N40P30K50 kg ha-1 , T15: 7.5 t RB ha-1 + N80P60K100 kg ha-1 , T16: 7.5 t RB ha-1 + N120P90K150 kg ha-1 . Results showed that the concentration, uptake and quality of seeds (oil and protein) of the crop increased with increasing rate of the amendments significantly (P<0.05) over the control and the variation between the treatments were also significant irrespective of the sources of amendments in most of the cases. Generally, combination of the treatments showed better performance than their individual application. Maximum values of NPKS concentration (%) in different organs of sunflower were 1.22, 0.35, 1.90, 0.18 for stem; 1.17, 0.35, 2.41, 0.16 for root; 3.98, 0.43, 4.28, 0.24 for leaf, 1.04, 0.65, 3.00, 0.22 for petiole; 2.16, 0.58, 2.21, 0.26 for inflorescence and 5.24, 0.83, 1.60, 0.47 for seed measured in treatments 5.0 t RB ha-1 + N120P90K150 kg ha-1 and 7.5 t RB ha-1 + N120P90K150 kg ha-1 in most of the cases. However, their uptake pattern also followed the same trend as in concentration and the highest values were found in those treatments in most of the cases. Significantly (P<0.05%) the highest content of oil (51.1%) in seed was measured in the treatment 5.0 t RB ha-1 + N120P90K150 kg ha-1 and protein (33.9%) was found in the treatment 5.0 t RB ha-1 +N80P60K100 kg ha-1 . Their lowest values were found in control for oil and in 2.5 t RB ha-1 for protein, which was lower than control treatment. The overall findings of this study indicated that rice bran in combination with chemical fertilizers could be applied to achieve better concentration and uptake in different organs, oil and protein content in seeds of sunflower.
Factors influencing adoption of high tunnels for tomato production in northeast district, Botswana
Creators: name: Badimo, Dandy
name: Badimo, Dandy
Publisher: name: Unknown
Year: 2020
Subjects: subject: Crop Production/Industries
subject: Botswana
subject: High tunnels technology
subject: Probit model
subject: Tomato

description: The study was carried out to investigate constraints and determinants of high tunnels adoption for tomato production in the North-East District of Botswana, using household survey data sourced directly from 116 horticultural farmers during the months of May and June 2017. Descriptive statistics and a binary probit regression model were employed to analyze constraints and determinants of high tunnels adoption for tomato production. The prohibitive cost of high tunnels, inadequate knowledge on high tunnels, inadequate capital and markets were identified as major constraints that hinder high tunnels adoption. The adoption of high tunnels was found to be positively influenced by years of education, access to extension services and farm size. The findings suggest that encouraging tunnel designers to consider constructing the structure using local materials could be ideal to cut down on the startup cost. Strengthening extension service and re-engineering of the current extension system is necessary to improve the adoption rate of the technology.
Blockchain and Machine Learning for Fraud Detection: A Privacy-Preserving and Adaptive Incentive Based Approach
Creators: name: Pranto, Tahmid Hasan
name: Hasib, Kazi Tamzid Akhter Md
name: Rahman, Tahsinur
name: Haque, AKM Bahalul
name: Islam, A. K. M. Najmul
name: Rahman, Rashedur M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cryptography and Security (cs.CR)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Financial fraud cases are on the rise even with the current technological advancements. Due to the lack of inter-organization synergy and because of privacy concerns, authentic financial transaction data is rarely available. On the other hand, data-driven technologies like machine learning need authentic data to perform precisely in real-world systems. This study proposes a blockchain and smart contract-based approach to achieve robust Machine Learning (ML) algorithm for e-commerce fraud detection by facilitating inter-organizational collaboration. The proposed method uses blockchain to secure the privacy of the data. Smart contract deployed inside the network fully automates the system. An ML model is incrementally upgraded from collaborative data provided by the organizations connected to the blockchain. To incentivize the organizations, we have introduced an incentive mechanism that is adaptive to the difficulty level in updating a model. The organizations receive incentives based on the difficulty faced in updating the ML model. A mining criterion has been proposed to mine the block efficiently. And finally, the blockchain network istested under different difficulty levels and under different volumes of data to test its efficiency. The model achieved 98.93% testing accuracy and 98.22% Fbeta score (recall-biased f measure) over eight incremental updates. Our experiment shows that both data volume and difficulty level of blockchain impacts the mining time. For difficulty level less than five, mining time and difficulty level has a positive correlation. For difficulty level two and three, less than a second is required to mine a block in our system. Difficulty level five poses much more difficulties to mine the blocks.
Post-translational modification in the regulation of the ubiquitin conjugating enzyme UBE2D3
Creators: name: Ito, Constance Masako
Publisher: name: Imperial College London
Year: 2019

description: UBE2D3 is a highly conserved and promiscuous E2 ubiquitin conjugating enzyme, which is known to function in processes that are important for normal development and dysregulated in cancers. This study sought to understand how the level of this protein is maintained and regulated by post-translational modifications in mouse embryonic stem cells (mESCs) and non-small cell lung carcinoma (NSCLC) cells. Conserved residues in the C-terminal α-helix and active site of UBE2D3, were found to be essential in the regulation of the protein stability in mESCs. These residues included C85, S94, T142, S138 and K144, whose mutation indirectly implicated phosphorylation, ubiquitination and nitrosylation, alongside possible mechanisms of protein interactions and direct structural effects. UBE2D3-S138 has been shown to be the site of phosphorylation by Aurora B kinase. This thesis presents evidence that phosphorylation of UBE2D3-S138 by Aurora B kinase in vitro, intrinsically disrupts the protein structure causing insolubility. Expression of phospho-mimetic mutants of UBE2D3 in mESCs confirmed the destabilising effect of S138 phosphorylation. This mechanism is essential for mouse embryonic development, and it has been shown to be required during differentiation into primitive endoderm, but was not critical in the formation of the germ layer lineages in this thesis. The stability of UBE2D3 is also dependent on the invariant K144. K144 is known to be ubiquitinated in vivo and when it was mutated to arginine in mESCs, UBE2D3 was downregulated and the mutant cells were incapable of effective differentiation into primitive endoderm and the lineages of the three germ layers. We conclude that the post-translational regulation of UBE2D3 protein levels, by conserved residues and their modification, is critical for the pluripotency of mESCs. The investigation of UBE2D3 in NSCLC cells revealed a similar mechanism of UBE2D3 destabilisation by Aurora B kinase, and a role for UBE2D3 activity in cell survival and proliferation.
Bioinorganic chemistry of aluminum, gallium. and indium complexes of 1-aryl-3-oxy-4-pyridinones
Creators: name: Zhang, Zaihui
Publisher: name: University of British Columbia
Year: 2008

description: A series of 1-aryl-3-hydroxy-2-methyl-4-pyridinones and tris( 1-aryl-3-oxy-2- methyl-4-pyridinonato)aluminum(III), gallium(III), and indium(III) complexes were prepared and characterized. The 3-hydroxy-4-pyridinones prepared have a variety of aryl substituents at the ring nitrogen atom (phenyl, p-tolyl, p-methoxyphenyl, and p nitrophenyl). The compounds were studied using a number of techniques including single crystal X-ray diffraction, variable temperature NMR spectroscopy, n-octanol/water partitioning, and potentiometric equilibrium measurements. The structures of 3-hydroxy-1-carboxymethyl-2-methyl-4-pyridinone (Hcmp), 3- hydroxy-1-(p-methoxyphenyl)-2-methyl-4-pyridinone (Hpap) and tris(3-oxy-2-methyl-1-p-tolyl)-4-pyridinonato)aluminum(III) (Al(ptp)3) and gallium(III) (Ga(ptp)3) complexes were determined by single crystal X-ray diffraction. A zwitterionic structure is formed in Hcmp as the ketone oxygen is protonated by the carboxyl proton. The metal complexes form rigidfac geometries incorporating hydrogen bonding water molecules which bridge the metal chelating ligand oxygen atoms. [more abstract]
Image analysis-based quantification of fungal sporulation by automatic conidia counting and gray value correlation
Creators: name: Muskat, Linda C.
name: Kerkhoff, Yannic
name: Humbert, Pascal
name: Nattkemper, Tim W.
name: Eilenberg, Jørgen
name: Patel, Anant V.
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: (Semi-)Automatic conidia counting
subject: Computer-assisted sporulation quantification
subject: Entomopathogenic fungi
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::579 Mikroorganismen, Pilze, Algen

description: The present work describes a new computer-assisted image analysis method for the rapid, simple, objective and reproducible quantification of actively discharged fungal spores which can serve as a manual for laboratories working in this context. The method can be used with conventional laboratory equipment by using bright field microscopes, standard scanners and the open-source software ImageJ. Compared to other conidia quantification methods by computer-assisted image analysis, the presented method bears a higher potential to be applied for large-scale sample quantities. The key to make quantification faster is the calculation of the linear relationship between the gray value and the automatically counted number of conidia that has only to be performed once in the beginning of analysis. Afterwards, the gray value is used as single parameter for quantification. The fast, easy and objective determination of sporulation capacity enables facilitated quality control of fungal formulations designed for biological pest control. • Rapid, simple, objective and reproducible quantification of fungal sporulation suitable for large-scale sample quantities. • Requires conventional laboratory equipment and open-source software without technical or computational expertise. • The number of automatically counted conidia can be correlated with the gray value and after initial calculation of a linear fit, the gray value can be applied as single quantification parameter.
Coining goldMEDAL: A New Contribution to Data Lake Generic Metadata Modeling
Creators: name: Scholly, Etienne
name: Sawadogo, Pegdwendé
name: Liu, Pengfei
name: Espinosa-Oviedo, Javier Alfonso
name: Favre, Cécile
name: Loudcher, Sabine
name: Darmont, Jérôme
name: Noûs, Camille
Publisher: name: arXiv
Year: 2021
Subjects: subject: Databases (cs.DB)
subject: FOS: Computer and information sciences

description: The rise of big data has revolutionized data exploitation practices and led to the emergence of new concepts. Among them, data lakes have emerged as large heterogeneous data repositories that can be analyzed by various methods. An efficient data lake requires a metadata system that addresses the many problems arising when dealing with big data. In consequence, the study of data lake metadata models is currently an active research topic and many proposals have been made in this regard. However, existing metadata models are either tailored for a specific use case or insufficiently generic to manage different types of data lakes, including our previous model MEDAL. In this paper, we generalize MEDAL's concepts in a new metadata model called goldMEDAL. Moreover, we compare goldMEDAL with the most recent state-of-the-art metadata models aiming at genericity and show that we can reproduce these metadata models with goldMEDAL's concepts. As a proof of concept, we also illustrate that goldMEDAL allows the design of various data lakes by presenting three different use cases.
[Northern Pomo field notes]
Creators: name: Guerrero, Edna
name: Vihman, Eero
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2015
Subjects: subject: pej
subject: Northern Pomo language

description: Northern Pomo field notebook labeled "6 EG 4": texts with titles "Earthquake", "Basketmaking", "Acorns", "At N. Fork", "Lg.", "Educ.", "Picking acorns".
Synthesis and Evaluation of Enantiopure HMPA Analogs in Samarium-Diiodide-Promoted Dearomatizations of N-Acylated Indole Derivatives
Creators: name: Rao, Chintada Nageswara
name: Reissig, Hans-Ulrich
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Cyclization
subject: Enantioselectivity
subject: Indole
subject: Phosphoramide
subject: Samarium diiodide
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: A series of (S)-proline-based enantiopure phosphorus triamide derivatives were prepared and evaluated as HMPA alternative in samarium diiodide cyclization reactions of N-acylated indole derivatives. The expected tricyclic indoline derivatives were generally obtained in good to excellent yields, however, the induced enantioselectivities were at best moderate. In our model reaction, the phosphorus triamide derivative with a (dimethyl)hydroxymethyl group at the stereogenic center provided the cyclization product in almost quantitative yield and with an enantiomeric excess of approximately 24 %. No separate proton source is required by applying this chiral Lewis base which was recovered in 93 % yield. Bulkier substituents at the stereogenic center did not furnish improved results. Although in our preliminary study only low to moderate enantioselectivities could be achieved, the observed fast conversions and the high yields demonstrate the basic suitability of chiral pyrrolidine-based phosphoramide Lewis bases in samarium(II)-induced reactions.
title: Synthesis and Characterization of Click-Activatable Circular Oligonucleotides for a novel CRISPR-Cas12a Biosensing Method
Creators: name: Reindl, Sarah
Publisher: name: TU Wien
Year: 2023
Subjects: subject: bioorthogonal chemistry
subject: click chemistry
subject: oligonucleotides
subject: nucleic acids
subject: CRISPR-Cas
subject: biosensing

description: Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprueft - gesperrte Arbeit (bis 2025-12-06+01:00)
description: Abweichender Titel nach Übersetzung der Verfasserin/des Verfassers
Optical Klystron Enhancement to SASE X-ray FELs
Creators: name: Ding, Yuantao
name: Emma, Paul
name: Huang, Zhirong
name: Kumar, Vinit
Publisher: name: arXiv
Year: 2006
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: The optical klystron enhancement to self-amplified spontaneous emission (SASE) free electron lasers (FELs) is studied in theory and in simulations. In contrast to a seeded FEL, the optical klystron gain in a SASE FEL is not sensitive to any phase mismatch between the radiation and the microbunched electron beam. The FEL performance with the addition of four optical klystrons located at the undulator long breaks in the Linac Coherent Light Source (LCLS) shows significant improvement if the uncorrelated energy spread at the undulator entrance can be controlled to a very small level. In addition, FEL saturation at shorter x-ray wavelengths (around 1.0 Å) within the LCLS undulator length becomes possible. We also discuss the application of the optical klystron in a compact x-ray FEL design that employs relatively low electron beam energy together with a short-period undulator.
description: 17 pages, 8 figures, submitted to Phys. Rev. ST Accel. Beams
Study of pesticide use on bitter gourd production at Jashore district
Creators: name: Hajong, P.
name: Rahman, M.S.
name: Islam, M.A.
name: Biswas, G.C.
name: Hajong, P.
name: Rahman, M.S.
name: Islam, M.A.
name: Biswas, G.C.
Publisher: name: Unknown
Year: 2020
Subjects: subject: Crop Production/Industries
subject: Pesticide
subject: IPM technology
subject: Bitter gourd
subject: Cost and return

description: The study was designed to assess the extent of pesticide use and profitability of bitter gourd production at farm level in selected areas of Jashore district during January-May, 2019. Average farm size was 0.79 ha and average bitter gourd cultivated area per farmer was 0.07 ha. Most of the farmer cultivated local variety, which is called Gajkorola and some farmer cultivated hybrid korola such as Gonggajoli, Tia and BARI Korola-1 variety. About ninetynine percent farmers sprayed insecticides and fungicides in their fields to protect crops from different insect pests and diseases. Thirty-nine percent farmers used pheromone trap for crop protection. A farmer averagely used 11.19 times spray in their fields and its range was 5- 18 times in a season. The average yield of bitter gourd was 16.74 t ha-1 for non-IPM farmer and 16.16 t ha-1 for IPM farmer. The average total cost of production of bitter gourd was Tk. 203984 ha-1 for non-IPM farmer and Tk. 191246 ha-1 for IPM farmer. Gross return was Tk. 389705 ha-1 and net return was Tk. 185721 ha-1 for non-IPM farmer. While, gross return of IPM farmer was Tk. 360828 ha-1 and net return was Tk. 169582 ha-1 . Benefit cost ratio was 1.91 and 1.89 for non-IPM and IPM farmer, respectively that means bitter gourd production was profitable. Cent percent farmer reported that IPM technology was time-consuming method and it was not only the measures to protect pests.
Control of particle trapping in a magnetoplasmonic nanopore
Creators: name: Maccaferri, Nicolò
name: Vavassori, Paolo
name: Garoli, Denis
Publisher: name: arXiv
Year: 2021
Subjects: subject: Applied Physics (physics.app-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Plasmonic nanopores are extensively investigated as single molecules detectors. The main limitations in plasmonic nanopore technology are the too fast translocation velocity of the molecule through the pore and the consequent very short analysis times, as well as the possible instabilities due to local heating. The most interesting approach to control the translocation of molecules and enable longer acquisition times is represented by the ability to efficiently trap and tune the motion of nanoparticles that can be used to tag molecules. Here, we theoretically investigate the performance of a magneto-plasmonic nanopore prepared with a thin layer of cobalt sandwiched between two gold layers. A nanopore is then coupled with a translocating magnetic nanoparticle. By setting the magnetic configuration of the cobalt layer around the pore by an external magnetic field, it is possible to generate a nanoscale magnetic tweezer to trap the nanoparticle at a specific point. Considering a 10 nm magnetite nanoparticle we calculate a trapping force up to 28 pN, an order of magnitude above the force that can be obtained with standard optical or plasmonic trapping approaches. Moreover, the magnetic force pulls the nanoparticle in close contact with the plasmonic nanopore's wall, thus enabling the formation of a nanocavity enclosing a deeply sub-wavelength confined electromagnetic field with an average field intensity enhancement up to 230 at near-infrared wavelengths. The presented hybrid magneto-plasmonic system points towards a strategy to improve nanopore-based biosensors for single-molecule detection and potentially for analysis of various biomolecules.
Unravelling a black box: an open-source methodology for the field calibration of small air quality sensors
Creators: name: Schmitz, Seán
name: Towers, Sherry
name: Villena, Guillermo
name: Caseiro, Alexandre
name: Wegener, Robert
name: Klemp, Dieter
name: Langer, Ines
name: Meier, Fred
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: small air quality sensors
subject: field calibration
subject: open-source methodology
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften

description: The last 2 decades have seen substantial technological advances in the development of low-cost air pollution instruments using small sensors. While their use continues to spread across the field of atmospheric chemistry, the air quality monitoring community, and for commercial and private use, challenges remain in ensuring data quality and comparability of calibration methods. This study introduces a seven-step methodology for the field calibration of low-cost sensor systems using reference instrumentation with user-friendly guidelines, open-access code, and a discussion of common barriers to such an approach. The methodology has been developed and is applicable for gas-phase pollutants, such as for the measurement of nitrogen dioxide (NO2) or ozone (O3). A full example of the application of this methodology to a case study in an urban environment using both multiple linear regression (MLR) and the random forest (RF) machine-learning technique is presented with relevant R code provided, including error estimation. In this case, we have applied it to the calibration of metal oxide gas-phase sensors (MOSs). Results reiterate previous findings that MLR and RF are similarly accurate, though with differing limitations. The methodology presented here goes a step further than most studies by including explicit transparent steps for addressing model selection, validation, and tuning, as well as addressing the common issues of autocorrelation and multicollinearity. We also highlight the need for standardized reporting of methods for data cleaning and flagging, model selection and tuning, and model metrics. In the absence of a standardized methodology for the calibration of low-cost sensor systems, we suggest a number of best practices for future studies using low-cost sensor systems to ensure greater comparability of research.
Discovery of a VHE gamma-ray source coincident with the supernova remnant CTB 37A
Creators: name: HESS Collaboration
name: Aharonian, F
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The supernova remnant (SNR) complex CTB 37 is an interesting candidate for observations with Very High Energy (VHE) gamma-ray telescopes such as H.E.S.S. In this region, three SNRs are seen. One of them is potentially associated with several molecular clouds, a circumstance that can be used to probe the acceleration of hadronic cosmic rays. This region was observed with the H.E.S.S. Cherenkov telescopes and the data were analyzed with standard H.E.S.S. procedures. Recent X-ray observations with Chandra and XMM-Newton were used to search for X-ray counterparts. The discovery of a new VHE gamma-ray source HESS J1714-385 coincident with the remnant CTB 37A is reported. The energy spectrum is well described by a power-law with a photon index of Gamma =2.30pm0.13 and a differential flux at 1 TeV of Phi_0 = (8.7 pm 1.0_{stat} pm 1.8_{sys})x10^{-13}cm^{-2}s^{-1}TeV^{-1}. The integrated flux above 1 TeV is equivalent to 3% of the flux of the Crab nebula above the same energy. This VHE gamma-ray source is a counterpart candidate for the unidentified EGRET source 3EG J1714-3857. The observed VHE emission is consistent with the molecular gas distribution around CTB 37A; a close match is expected in a hadronic scenario for gamma-ray production. The X-ray observations reveal the presence of thermal X-rays from the NE part of the SNR. In the NW part of the remnant, an extended non-thermal X-ray source, CXOU J171419.8-383023, is discovered as well. Possible connections of the X-ray emission to the newly found VHE source are discussed.
description: 9 pages, 5 figures, accepted by A&A, Fig4&5 have been revised, the CO contours have been added, some revisions in the X-ray analysis part, a table of X-ray point-like sources have been added
Fluctuating magnetism of Co- and Cu-doped NaFeAs
Creators: name: Pelliciari, Jonathan
name: Ishi, Kenji
name: Xing, Lingyi
name: Wang, Xiancheng
name: Jin, Changqing
name: Schmitt, Thorsten
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report an x-ray emission spectroscopy (XES) study of the local fluctuating magnetic moment ($μ_{bare}$) in $\mathrm{NaFe_{1-x}Co_{x}As}$ and $\mathrm{NaFe_{1-x}Cu_{x}As}$. In NaFeAs, the reduced height of the As ions induces a local magnetic moment higher than $\mathrm{Ba_2As_2}$, despite lower T$_N$ and ordered magnetic moment. As NaFeAs is doped with Co $μ_{bare}$ is slightly reduced, whereas Cu doping leaves it unaffected, indicating a different doping mechanism: based on electron counting for Co whereas impurity scattering dominates in the case of Cu. Finally, we observe an increase of $μ_{bare}$ with temperature in all samples as observed in electron- and hole-doped $\mathrm{BaFe_2As_2}$. Since both Co and Cu doping display superconductivity, our findings demonstrate that the formation of Cooper pairs is not connected with the complete loss of fluctuating paramagnetic moments.
description: 17 pages, 4 figures, 1 table
Topologically-mediated energy release by relativistic antiferromagnetic solitons
Creators: name: Otxoa, R. M.
name: Rama-Eiroa, R.
name: Roy, P. E.
name: Tatara, G.
name: Chubykalo-Fesenko, O.
name: Atxitia, Unai
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Magnetic texture
subject: Spintronics
subject: Ultrafast magnetization dynamics
subject: 500 Naturwissenschaften und Mathematik::530 Physik::530 Physik

description: Magnetic solitons offer functionalities as information carriers in multiple spintronic and magnonic applications. However, their potential for nanoscale energy transport has not been revealed. Here we demonstrate that antiferromagnetic solitons, e.g., domain walls, can uptake, transport, and release energy. The key for this functionality resides in their relativistic kinematics; their self-energy increases with velocity due to Lorentz contraction of the soliton and their dynamics can be accelerated up to the effective speed of light of the magnetic medium. Furthermore, their classification in robust topological classes allows us to selectively release this energy back into the medium by colliding solitons with opposite topology. Our work uncovers important energy-related aspects of the physics of antiferromagnetic solitons and opens up the attractive possibility for spin-based nanoscale and ultrafast energy transport devices.
Place-based perceptions, resilience and adaptation to climate change by smallholder farmers in rural South Africa
Creators: name: Tesfuhuney, W.A.
name: Mbeletshie, E.H.
name: Tesfuhuney, W.A.
name: Mbeletshie, E.H.
Publisher: name: Unknown
Year: 2020
Subjects: subject: Environmental Economics and Policy
subject: Smallholders
subject: Farmers’ perception
subject: Adaptation
subject: Resilience
subject: Climate change

description: Unprecedented global climate change caused by human actions is becoming a challenge to agricultural systems’ ability to meet and sustain production demands for food and raw materials for the increasing world population. Climate change has not spared the district, resulting in extreme weather events such as droughts, erratic rainfalls and increasing frosty winter days within the district. Smallholder agriculture in Sub-Saharan Africa is mainly dependent on rainfed agriculture, which has increased production uncertainty due to the increasing variability of climate. This study assesses the management of adaptation and resilience strategies by smallholder farmers in Joe Gqabi District Municipality in Eastern Cape, South Africa. The study revealed a significant response to climate variability by smallholder farmers, which involved the adoption of numerous adaptation and resilience strategies. The choice of resilience and adaptation strategies among community members is influenced by a diversity of factors amongst which are; household demographic characteristics, access to information and technology, household assets endowment and farmers’ perception of climate change. Results from the study also reveal a lack of public and private institutional support to the farmers hence the lack of in-depth awareness of climate change by these farmers. Drawing on the results and conclusions, the study recommends strengthening the capacity of farmers and institutions for identifying and assessing climate change. There is an urgent need for proactive management of climate change through sustaining those attributes that are important for production (resilience) and developing new socio-ecological configurations that function effectively under new conditions (adaptation). Implementation of policy interventions that build on farmers’ existing knowledge is also critical.
A photochemical study of dibenzobarrelene amides and ester-amides: solution and solid state rearrangements
Creators: name: Rattray, Alistair Graham McLeod
Publisher: name: University of British Columbia
Year: 2008

description: The photochemical reactions of various dibenzobarrelene acyl derivatives has been investigated in solution and in the solid state. These derivatives consisted of monoamides, symmetrical diamides, mixed ester-amides, and mixed ester-thioesters. The two types of reactions found in the irradiation of these systems were the di-π-methane rearrangement and/or hydrogen abstraction. Photolysis of dibenzobarrelene monoamides in solution and in the solid state gave a symmetrical dibenzosemibullvalene photoproduct. Two monoamides (R,R = Bz and R,R = iPr) gave ring-fused spiro β-lactam analogues of the starting materials in addition to the semibullvalene product. These two amides also gave an ethano-bridged monosubstituted amide photoproduct as did a third monoamide (R,R = Et). Photolysis of all monoamides in the solid state resulted in the formation of semibullvalenes only. X-ray crystallographic analysis of the diethyl and the di-iso-propyl starting materials were performed in order to correlate the lack of hydrogen abstraction in solid state irradiations with the geometric constraints of the crystalline starting material. An X-ray crystallographic analysis of the dibenzyl amide-derived β lactam was also performed in order to establish the relationships between the various stereochemical centres in the molecule. A series of symmetrical diamides was prepared and photolyzed in solution and in the solid state. All diamides gave a single semibullvalene photoproduct upon irradiation in solution. Two of the starting materials (N,N-dimethyl and N,N-diethyl) also reacted rapidly and efficiently in the solid state to give the semibullvalene product, whereas two others (N-methyl and N-ethyl) were found to be very unreactive in the solid state. [more abstract]
Effect of different amounts of feeds on growth and production of fishes in pond polyculture
Creators: name: Sultana, S.
name: Rahman, M.S.
name: Jackshay, K.A.
name: Hasan, K.
name: Sultana, S.
name: Rahman, M.S.
name: Jackshay, K.A.
name: Hasan, K.
Publisher: name: Unknown
Year: 2020
Subjects: subject: Livestock Production/Industries
subject: Amounts of feed
subject: Production of fish
subject: Environmental factors
subject: Pond
subject: Polyculture

description: An experiment was carried out to evaluate the effects of different amounts of supplementary feeds on growth and production of fishes in polyculture where four different species such as rui (Labeo rohita), mrigal (Cirrhinus mrigala), common carp (Cyprinus carpio) and tilapia (Oreochromis niloticus) were cultured in 6 ponds under three treatments, each with two replications. Eighty fish per decimal were stocked along with the stocking ratio of 1:1:1:1 in all the treatments. Supplementary feeds of rice bran and wheat bran (1:1), at the amount of 5% of body weight were applied in 2 ponds (treatment I) as well as at the amount of 3% of body weight were used in 2 ponds (treatment II) and 2 ponds (treatment III) were as control where no supplementary feed was used. Urea and T.S.P were applied fortnightly at the rate of 60 g decimal-1 and 90 g decimal-1 , respectively under all treatments. Physico-chemical and biological factors such as air and water temperature, transparency, rainfall, pH, dissolved oxygen, free CO2, total alkalinity, PO4-P and NO3-N, phytoplankton and zooplankton were studied fortnightly and the limnological conditions were more or less similar in the experimental ponds under three treatments. The calculated gross and net fish productions of fishes under treatment I, treatment II and treatment III were 8.87 and 7.33 ton ha-1 yr-1 , 7.12 and 5.58 ton ha-1 yr-1 and 4.69 and 3.16 ton ha-1 yr-1 , respectively. Percent increased of net fish productions of treatment I and treatment II were 231.97% and 176.59% higher than that of treatment III (control). The present study reveals that supplementary feeding in fish culture should be done along with fertilization because supplementary feeds are very important to enhance growth of fishes significantly.
Bioinformatics: scope and challenges in aquaculture research of Bangladesh- a review
Creators: name: Rana, K.M.S.
name: Ahammad, K.
name: Salam, M.A.
name: Rana, K.M.S.
name: Ahammad, K.
name: Salam, M.A.
Publisher: name: Unknown
Year: 2020
Subjects: subject: Agribusiness
subject: Bioinformatics
subject: FOS: Computer and information sciences
subject: Aquaculture
subject: Bangladesh

description: Bioinformatics is one of the ongoing trends of biological research integrating gene based information and computational technology to produce new knowledge. It works to synthesize complex biological information from multiomics data (results of high throughput technologies) by employing a number of bioinformatics tools (software). User convenience and availability are the determining factors of these tools being widely used in bioinformatics research. BLAST, FASTA (FAST-All), EMBOSS, ClustalW, RasMol and Protein Explorer, Cn3D, Swiss PDB viewer, Hex, Vega, Bioeditor etc. are commonly operated bioinformatics software tools in fisheries and aquaculture research. By default, these software tools mine and analyze a vast biological data set using the available databases. However, aquaculture scientists can use bioinformatics for genomic data manipulation, genome annotation and expression profiling, molecular folding, modeling, and design as well as generating biological network and system biology. Therefore, they can contribute in specified fields of aquaculture such as disease diagnosis and aquatic health management, fish nutritional aspects and culture-able strain development. Although having huge prospects, Bangladesh is still in infancy of applying bioinformatics in aquaculture research with limited resources. Research council at national level should be formed to bring all the enthusiastic scientists and skilled manpower under a single umbrella and facilitate to contribute in a collaborative platform. Besides, fully-fledged bioinformatics degree should be launched at University levels to produce knowledgeable and trained work force for future research. This review was attempted to shed light on bioinformatics, as young integrated field of bio-computational research, and its significance in aquaculture research of Bangladesh.
Bow shock interaction experiments in a magnetised collisional plasma
Creators: name: Russell, Daniel Robert
Publisher: name: Imperial College London
Year: 2021

description: This thesis reports on shock interaction experiments at the MAGPIE pulsed power facility. Bow shocks are produced by placing cylindrical obstacles into the supersonic, super- Alfvénic and super-fast-magnetosonic plasma outflow from an inverse wire array z-pinch. The wire array provides a continuous source of plasma for ~ 500 ns with a velocity of ~ 50 km/s which advects a dynamically significant magnetic field of ~ 1.5 - 2.5 T. The geometry of the experiment allows good diagnostic access to the bow shocks and obstacles are fielded in pairs so that neighbouring bow shocks interact. The complex shock structure which emerges is a result of the resistive diffusion length being much larger than the collisional mean free path. Two types of shock are seen. One is characterised by a large shock transition length and very little heating and is a sub-critical resistive dissipative shock. This is observed to form as a single shock across both obstacles. The second are two shocks which form close to the obstacles and are downstream of the resistive dissipative shock. These exhibit substantial heating and have a shorter transition length. We interpret these to be hydrodynamic-like. The experiments are diagnosed with laser interferometry, Faraday rotation imaging, optical Thomson scattering and optical self-emission imaging which provide detailed time and space resolved measurements of the plasma parameters, including inside the resistive dissipative shock transition. An experimental validation of the Faraday rotation imaging diagnostic is presented to evaluate analysis techniques. Experiments with different plasma materials are compared, which demonstrates the dependence of the resistive dissipative shock transition length on the resistive diffusion length. The experimental results are compared with AstroBEAR simulations including new simulation results which include a magnetic field in such systems for the first time. Preliminary results show good agreement with our interpretation of the experiments.
Magnetic Flows on Homogeneous Spaces
Creators: name: Bolsinov, Alexey V.
name: Jovanovic, Bozidar
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 70H06, 37J35, 53D25

description: We consider magnetic geodesic flows of the normal metrics on a class of homogeneous spaces, in particular (co)adjoint orbits of compact Lie groups. We give the proof of the non-commutative integrability of flows and show, in addition, for the case of (co)adjoint orbits, the usual Liouville integrability by means of analytic integrals. We also consider the potential systems on adjoint orbits, which are generalizations of the magnetic spherical pendulum. The complete integrability of such system is proved for an arbitrary adjoint orbit of a compact semisimple Lie group.
description: 21 pages, minor changes, final version, to appear in Commentarii Mathematici Helvetici
From a locality-principle for new physics to image features of regular spinning black holes with disks
Creators: name: Eichhorn, Astrid
name: Held, Aaron
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Current observations present unprecedented opportunities to probe the true nature of black holes, which must harbor new physics beyond General Relativity to provide singularity-free descriptions. To test paradigms for this new physics, it is necessary to bridge the gap all the way from theoretical developments of new-physics models to phenomenological developments such as simulated images of black holes embedded in astrophysical disk environments. In this paper, we construct several steps along this bridge. We construct a novel family of regular black-hole spacetimes based on a locality principle which ties new physics to local curvature scales. We then characterize these spacetimes in terms of a complete set of curvature invariants and analyze the ergosphere and both the outer event as well as distinct Killing horizon. Our comprehensive study of the shadow shape at various spins and inclinations reveals characteristic image features linked to the locality principle. We also explore the photon rings as an additional probe of the new-physics effects. A simple analytical disk model enables us to generate simulated images of the regular spinning black hole and test whether the characteristic image-features are visible in the intensity map.
description: 25 pages (including 12 figures) + two appendices, references, and a supplementary file
Three Dimensional Simulations of White Dwarf Mergers and Turbulently-Driven Detonation
Creators: name: Fisher, Robert
name: Kashyap, Rahul
name: Pritom Mozumdar
name: Zenati, Yossef
name: Tazkera Haque
name: Casabona, Gabriel
name: Lorén-Aguilar, Pablo
name: García-Berro, Enrique
Publisher: name: Zenodo
Year: 2019

description: While the stellar progenitors of Type Ia supernovae (SNe Ia) remain a subject of active investigation, recent multi-wavelength observations of SNe Ia have tightly constrained near-Chandrasekhar mass (near-Mch) single-degenerate (SD) SNe Ia. In particular, the most extensive set of non-detections of nebular H-alpha from SNe Ia of 110 events of all classes (Tucker et al, 2019) guide us to seriously consider white dwarf mergers as the origin not only of normal SNe Ia, but also of SNe Ia types previously considered to originate from SDs -- ranging from underluminous SNe Iax to bright 91Ts. In this talk, I will present the first three-dimensional simulations of CO and ONe WD mergers and demonstrate that these may lead to very faint, rapid transients with possible connections to SNe Iax. Additionally, I will also present new three-dimensional simulations of CO WD binaries with thin He layers, and explore whether surface He detonations yield detonations of the underlying CO primary cores. Lastly, I will discuss new physical insights into the crucial physical process of turbulently-driven detonation initiation, which underlies all major SNe Ia channels.
A model of the light curves of Gamma-Ray Bursts
Creators: name: Lei, W. H.
name: Wang, D. X.
name: Gong, B. P.
name: Huang, C. Y.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: An extreme Kerr black hole (BH) surrounded by a precessing disk is invoked to explain the light curves of gamma-ray bursts (GRBs) based on the coexistence of the Blandford-Znajek (BZ) and the magnetic coupling (MC) processes. The overall shape of the light curves and the duration of GRBs are interpreted by the evolution of the half-opening angle of the magnetic flux on the BH horizon, and the complex temporal structures are modulated by the precession and nutation of the jet powered by the BZ process. The time profile of the emission exhibits a fast rise and a slow decay due to the effect of the evolution of the half-opening angle. The light curves of several GRBs are well fitted by this model with only six free parameters.
description: 8 pages, 8 figures. Accepted for publication in A&A
Thermodynamics and Self-organization of Strongly Coupled Coulomb Clusters: An Experimental Study
Creators: name: Hariprasad, M. G.
name: Bandyopadhyay, P.
name: Arora, Garima
name: Sen, A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: In this experimental work, the thermodynamics and self-organization of classical two-dimensional Coulomb clusters are studied as a function of the cluster size. The experiments are carried out in a DC glow discharge Argon plasma in the Dusty Plasma Experimental (DPEx) device for clusters with different number of particles. Hexagonal symmetry around each individual particle is quantified using the local orientational order parameter ($|{ψ_6}|$) for all the configurations. The screened Coulomb coupling parameter, which plays a key role in determining the thermodynamic nature of a Coulomb cluster, is estimated using Langevin dynamics and found to be sensitive to the number of particles present in the cluster. In addition, the process of self-organization and the dynamics of individual particles of the cluster as it changes from a metastable state to the ground state are examined through the estimation of dynamic entropy. Our findings suggest an intimate link between the configurational ordering and the thermodynamics of a strongly coupled Coulomb cluster system - an insight that might be of practical value in analysing and controlling the micro dynamics of a wider class of finite systems.
description: The paper contains nine pages and eight figures