cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Implication of size-controlled graphite nanosheets as building blocks for thermal conductive three-dimensional framework architecture of nanocarbons
Creators: name: Shin, Keun-Young
name: Jin, Sung Gook
name: Sung, Bong June
name: Lee, Sang-Soo
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Space Science
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Evolutionary Biology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Inorganic Chemistry
subject: Science Policy

description: Preparation of three-dimensional (3-D) networks has received significant attention as an effective approach for applications involving transport phenomena, such as thermal management materials, and several nanomaterials have been examined as potential building blocks of 3-D networks for the improvement of heat conduction in polymer nanocomposites. For that purpose, nanocarbons such as graphene and graphite nanoplatelets have been spotlighted as suitable filler materials because of their excellent thermal conductivities (ca. 102–103 W·(m·K)−1 along their lateral axes) and morphological merits. However, the implications of morphological features such as the lateral length and thickness of the graphene or graphene-like materials have not yet been identified. In this study, a controlled dissociation of bulk graphite to graphite nanosheets (GNSs) using a low-cost, eco-friendly bead mill process was extensively examined and, when configured in a 3-D framework architecture formation, the size-controlled GNSs demonstrated that the thermal conductivities of a 3-D interconnected framework of GNSs and the corresponding polymer nanocomposite were intimately correlated with the size of the GNSs, thus demonstrating the successful preparation of an efficient thermal management material without highly sophisticated efforts. The capability of controlling the lateral size and thickness of the GNSs as well as the use of a 3-D interconnected framework architecture should greatly assist the commercialization of high-quality graphene-based thermal management materials in a scalable production process.
Final. Discussion Paper. Mechanization in Rice Farming - Lessons Learned from Other Countries. SENT TO ARF 10th Feb 2014.docx
Creators: name: Hegazy, Rashad
Publisher: name: figshare
Year: 2017
Subjects: subject: 70199 Agriculture, Land and Farm Management not elsewhere classified
subject: FOS: Other agricultural sciences

description: Lessons
Black Hole Weather Forecasting with Deep Learning: A Pilot Study
Creators: name: Duarte, Roberta
name: Nemmen, Rodrigo
name: Navarro, João Paulo
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In this pilot study, we investigate the use of a deep learning (DL) model to temporally evolve the dynamics of gas accreting onto a black hole in the form of a radiatively inefficient accretion flow (RIAF). We have trained a machine to forecast such a spatiotemporally chaotic system -- i.e. black hole weather forecasting -- using a convolutional neural network (CNN) and a training dataset which consists of numerical solutions of the hydrodynamical equations, for a range of initial conditions. We find that deep neural networks seem to learn well black hole accretion physics and evolve the accretion flow orders of magnitude faster than traditional numerical solvers, while maintaining a reasonable accuracy for a long time. For instance, CNNs predict well the temporal evolution of a RIAF over a long duration of $8\times 10^4 GM/c^3$, which corresponds to 80 dynamical times at $r=100 GM/c^2$. The DL model is able to evolve flows from initial conditions not present in the training dataset with good accuracy. Our approach thus seems to generalize well. Once trained, the DL model evolves a turbulent RIAF on a single GPU four orders of magnitude faster than usual fluid dynamics integrators running in parallel on 200 CPU cores. We speculate that a data-driven machine learning approach should be very promising for accelerating not only fluid dynamics simulations, but also general relativistic magnetohydrodynamic ones.
description: Accepted 2022 March 3. Received 2022 February 10; in original form 2021 January 11 (15 pages, 18 figures)
The Higgs mechanism and geometrical flows for two-manifolds
Creators: name: Cartas-Fuentevilla, R.
name: Herrera-Aguilar, A.
name: Berra-Montiel, J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Using Perelman's approach for geometrical flows in terms of an entropy functional, the Higgs mechanism is studied dynamically along flows defined in the space of parameters and in fields space. The model corresponds to two-dimensional gravity that incorporates torsion as the gradient of a Higgs field, and with the reflection symmetry to be spontaneously broken. The results show a discrete mass spectrum, and the existence of a mass gap between the Unbroken Exact Symmetry and the Spontaneously Broken Symmetry scenarios. In the later scenario, the geometries at the degenerate vacua correspond to conformally flat manifolds without torsion; twisted two-dimensional geometries are obtained by building perturbation theory around a ground state; the tunneling quantum probability between vacua is determined along the flows.
description: 15 pages, 3 figures
Consistent equivalence principle tests with fast radio bursts
Creators: name: Reischke, Robert
name: Hagstotz, Steffen
name: Lilow, Robert
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Fast radio bursts (FRBs) are astrophysical transients of still debated origin. So far several hundred events have been detected, mostly at extragalactic distances, and this number is expected to grow significantly over the next years. The radio signals from the burst experience dispersion as they travel through the free electrons along the line-of-sight characterised by the dispersion measure (DM) of the radio pulse. In addition, each photon also experiences a gravitational Shapiro time delay while travelling through the potentials generated by the large-scale structure. If the equivalence principle (EP) holds, the Shapiro delay is the same for photons of all frequencies. In case the EP is broken, one would expect an additional dispersion to occur which could be either positive or negative for individual sources. Here we suggest to use angular statistics of the DM fluctuations to put constraints on the EP parametrized by the post-Newtonian parameter $γ$. Previous studies suffer from the problem that the gravitational potential responsible for the delay diverges in a cosmological setting, which our approach avoids. We carry out a forecast for a population of FRBs observable within the next years and show that any significant detection of the DM angular power spectrum will place constraints on the EP that are by a few orders of magnitude more stringent than current limits.
description: 6 pages, 2 figures
Gradient Alignment for Cross-Domain Face Anti-Spoofing
Creators: name: Le, Binh M.
name: Woo, Simon S.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Recent advancements in domain generalization (DG) for face anti-spoofing (FAS) have garnered considerable attention. Traditional methods have focused on designing learning objectives and additional modules to isolate domain-specific features while retaining domain-invariant characteristics in their representations. However, such approaches often lack guarantees of consistent maintenance of domain-invariant features or the complete removal of domain-specific features. Furthermore, most prior works of DG for FAS do not ensure convergence to a local flat minimum, which has been shown to be advantageous for DG. In this paper, we introduce GAC-FAS, a novel learning objective that encourages the model to converge towards an optimal flat minimum without necessitating additional learning modules. Unlike conventional sharpness-aware minimizers, GAC-FAS identifies ascending points for each domain and regulates the generalization gradient updates at these points to align coherently with empirical risk minimization (ERM) gradient updates. This unique approach specifically guides the model to be robust against domain shifts. We demonstrate the efficacy of GAC-FAS through rigorous testing on challenging cross-domain FAS datasets, where it establishes state-of-the-art performance. The code is available at https://github.com/leminhbinh0209/CVPR24-FAS.
Rotor-routing reachability is easy, chip-firing reachability is hard
Creators: name: Tóthmérész, Lilla
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 68Q17, 05C50, 05C85

description: Chip-firing and rotor-routing are two well-studied examples of abelian networks. We study the complexity of their respective reachability problems. We show that the rotor-routing reachability problem is decidable in polynomial time, and we give a simple characterization of when a chip-and-rotor configuration is reachable from another one. For chip-firing, it has been known that the reachability problem is in P if we have a class of graphs whose period length is polynomial (for example, Eulerian digraphs). Here we show that in the general case, chip-firing reachability is hard in the sense that if the chip-firing reachability problem were in P for general digraphs, then the polynomial hierarchy would collapse to NP. We encode graphs by their adjacency matrix, and we encode ribbon structures "succinctly", only remembering the number of consecutive parallel edges.
Braneworld-Klein-Gordon system in the framework of gravitational decoupling
Creators: name: León, P.
name: Sotomayor, A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We analyze the effective field equations of the Randall-Sundrum braneworld coupled with a Klein-Gordon scalar field through the minimal geometric deformation decoupling method (MGD-decoupling). We introduce two different ways to apply the MGD-decoupling method to obtain new solutions for this enlarged system. We also compare the behavior of the new solutions with those obtained directly from the Randall-Sumdrum braneworld without coupling to the scalar field.
description: 13 pages, 6 figure
Two-Step Estimation of Incomplete Information Social Interaction Models with Sample Selection
Creators: name: Hoshino, Tadao
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Medicine
subject: Biotechnology
subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Science Policy

description: In this study, we consider linear social interaction models under incomplete information that allow for missing outcome data due to sample selection. For model estimation, assuming that each individual forms his/her belief about the other members' outcomes based on rational expectations, we propose a two-step series nonlinear least squares estimator. Both the consistency and asymptotic normality of the estimator are established. As an empirical illustration, we apply the proposed model and method to National Longitudinal Study of Adolescent Health (Add Health) data to examine the impacts of friendship interactions on adolescents' academic achievements. We provide empirical evidence that the interaction effects are important determinants of grade point average and that controlling for sample selection bias has certain impacts on the estimation results. Supplementary materials for this paper are available online.
Additional file 2 of Effect of nicastrin on hepatocellular carcinoma proliferation and apoptosis through PI3K/AKT signalling pathway modulation
Creators: name: Wang, Xicheng
name: Wang, Xining
name: Xu, Yunxiuxiu
name: Yan, Maolin
name: Li, Wenxin
name: Chen, Jie
name: Chen, Tao
Publisher: name: figshare
Year: 2020
Subjects: subject: Biochemistry
subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Chemical Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Cancer

description: Additional file 2: Table S1. Relationship between NCSTN expression and clinicopathological characteristics in 370 HCC patients from TCGA database.
Needing to Belong: First Practice Placement Experiences of Children’s Nursing Students
Creators: name: Brady, Mary
name: Price, Jayne
name: Bolland, Rachael
name: Finnerty, Gina
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Medicine
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Science Policy

description: This study examines first year children’s nursing students’ anxieties before their first practice placement and their support needs during that time. Strategies to address needs are highlighted. A questionnaire was completed by children’s nursing students (n = 21) before their initial practice placement to establish their expectations and concerns. A subgroup (n = 5) took part in a focus group following placement to establish consensus around the support that helped and what could help future students prepare for first placement. The resultant data indicated the importance of students having a sense of belonging to their practice placement, trusting website information, induction days, and the involvement of a more senior student in their preparation, in addition to facilitative mentors. Using similar methodology to that used with students, a subgroup of professional staff took part in two focus groups (FG1 n = 5, FG2 n = 4) to establish consensus around support initiatives using areas identified by students as priorities that could better facilitate this initial practice placement. Although commonalities existed within both students and professionals, some differences were highlighted. A student’s first practice placement is of utmost importance in affirming their choice to study nursing. Academic and clinical staff play a crucial part in this decision-making.
Potential functions of LEA proteins from the brine shrimp Artemia franciscana – anhydrobiosis meets bioinformatics
Creators: name: Janis, Brett
name: Uversky, Vladimir N.
name: Menze, Michael A.
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Biophysics
subject: Biochemistry
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Cancer
subject: Inorganic Chemistry
subject: FOS: Chemical sciences

description: Late embryogenesis abundant (LEA) proteins are a large group of anhydrobiosis-associated intrinsically disordered proteins, which are commonly found in plants and some animals. The brine shrimp Artemia franciscana is the only known animal that expresses LEA proteins from three, and not only one, different groups in its anhydrobiotic life stage. The reason for the higher complexity in the A. franciscana LEA proteome (LEAome), compared with other anhydrobiotic animals, remains mostly unknown. To address this issue, we have employed a suite of bioinformatics tools to evaluate the disorder status of the Artemia LEAome and to analyze the roles of intrinsic disorder in functioning of brine shrimp LEA proteins. We show here that A. franciscana LEA proteins from different groups are more similar to each other than one originally expected, while functional differences among members of group three are possibly larger than commonly anticipated. Our data show that although these proteins are characterized by a large variety of forms and possible functions, as a general strategy, A. franciscana utilizes glassy matrix forming LEAs concurrently with proteins that more readily interact with binding partners. It is likely that the function(s) of both types, the matrix-forming and partner-binding LEA proteins, are regulated by changing water availability during desiccation.
On the Analyticity of Critical Points of the Generalized Integral Menger Curvature in the Hilbert Case
Creators: name: Steenebrügge, Daniel
name: Vorderobermeier, Nicole
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35A20 (Primary) 35A10, 35B65, 57K10 (Secondary)

description: We prove the analyticity of smooth critical points for generalized integral Menger curvature energies $\mathrm{intM}^{(p,2)}$, with $p \in (\tfrac 73, \tfrac 83)$, subject to a fixed length constraint. This implies, together with already well-known regularity results, that finite-energy, critical $C^1$-curves $γ: \mathbb{R}/\mathbb{Z} \to \mathbb{R}^n$ of generalized integral Menger curvature $\mathrm{intM}^{(p,2)}$ subject to a fixed length constraint are not only $C^\infty$ but also analytic. Our approach is inspired by analyticity results on critical points for O'Hara's knot energies based on Cauchy's method of majorants and a decomposition of the first variation. The main new idea is an additional iteration in the recursive estimate of the derivatives to obtain a sufficient difference in the order of regularity.
description: 31 pages
Nitrogen addition frequency and propagule pressure influence solidago canadensis invasion into native plant community
Creators: name: Liu, Xuan-Shao
name: Cai, Jing-Fang
name: Liu, Lin
name: Sun, Kai
name: Jiang, Fan
name: Shen, Yi-Luan
name: a, Si-Ha
name: Li, Hong-Li
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Ecology
subject: FOS: Biological sciences
subject: Marine Biology
subject: Plant Biology

description: Propagule pressure (i.e., the number of propagules) has long been recognized to play an essential role in plant invasion. But it is not clear whether propagule pressure influences the invasion of exotic plants into native plant communities when different frequencies of nitrogen are added. We established an experiment with three plant communities that included native plant communities alone (four grasses, two legumes and two forbs) or native plant communities with one or five invasive plants, Solidago canadensis, under three frequencies of nitrogen addition (no addition or low or high addition with the same amount). High propagule pressure significantly enhanced the biomass and relative dominance index of S. canadensis. Moreover, high propagule pressure only decreased the total and aboveground biomass of the legumes. However, the competitive effect between S. canadensis and the native community and biomass of the whole native community varied according to different frequencies. Overall, high propagule pressure encouraged invasion by S. canadensis, while alow nitrogen frequency was advantageous for the native community to resist invasion in this experiment.The results provide a scientific basis to manage and control the invasion of S. canadensis.
MicroCT Dataset of mouse tibiae for DVC precision analyses (repeated scans ex vivo and in vivo)
Creators: name: Dall'Ara, Enrico
Publisher: name: The University of Sheffield
Year: 2017
Subjects: subject: 110601 Biomechanics
subject: FOS: Health sciences
subject: 90302 Biomechanical Engineering
subject: FOS: Medical engineering

description: Database of the images (repeated scans of mouse tibiae obtained in vivo and ex vivo) used in:
Precision of DVC approaches for strain analysis in bone imaged with μCT at different dimensional levels. by: Enrico Dall'ara, Marta Peña-Fernández, Marco Palanca, Mario Giorgi, Luca Cristofolini, Gianluca TozziOriginal Research, Front. Mater. - Mechanics of Materials, 2017
The images related to the precision of DVC applied to the mouse tibiae are too large to be uploaded in figshare so please contact the corresponding author at: e.dallara@sheffield.ac.uk or the Project Management Office at: pmo@insigneo.org if interested in working on the files.
The files are stored in the University of Sheffield file-store at the link:https://web-unidrive.sheffield.ac.uk/shared/multisim2/WP7/Mario_Giorgi/DVC_Tibia_Precision_Study
Computational DNA binding studies of (–)-epigallocatechin-3-gallate
Creators: name: Galindo-Murillo, Rodrigo
name: Cheatham, Thomas E.
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: Cell Biology
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer

description: The catechin family of molecules that are present in the leaves of green tea has been under investigation since the antioxidant and anti-inflammatory properties of tea were discovered. Among multiple proposed therapeutic targets of these molecules, the direct interaction with nucleic acids has been proposed and experimentally observed but without clear knowledge about the potential binding modes between these ligands and DNA. One of these catechin structures, (–)-epigallocatechin gallate (EGCG), has three aromatic rings that could interact with double-stranded DNA via terminal base-pair stacking, intercalation, or through groove binding. Using enhanced sampling techniques and molecular dynamics simulations, we have found a stable complex between the EGCG ligand and DNA through intercalation of the trihydroxybenzoate aromatic ring and an ApC step. Moreover, we have calculated the absorption spectra of four possible binding modes and compared these to absorption profiles reported in the literature, and explored the possible DNA sequence preference for the EGCG ligand to bind. Our results suggest that an intercalative mode of interaction through the major groove is possible between the EGCG ligands and DNA with apparently very little DNA sequence selectivity.
Analytic Filter Function Derivatives for Quantum Optimal Control
Creators: name: Le, Isabel Nha Minh
name: Teske, Julian D.
name: Hangleiter, Tobias
name: Cerfontaine, Pascal
name: Bluhm, Hendrik
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Auto-correlated noise appears in many solid state qubit systems and hence needs to be taken into account when developing gate operations for quantum information processing. However, explicitly simulating this kind of noise is often less efficient than approximate methods. Here, we focus on the filter function formalism, which allows the computation of gate fidelities in the presence of auto-correlated classical noise. Hence, this formalism can be combined with optimal control algorithms to design control pulses, which optimally implement quantum gates. To enable the use of gradient-based algorithms with fast convergence, we present analytically derived filter function gradients with respect to control pulse amplitudes, and analyze the computational complexity of our results. When comparing pulse optimization using our derivatives to a gradient-free approach, we find that the gradient-based method is roughly two orders of magnitude faster for our test cases. We also provide a modular computational implementation compatible with quantum optimal control packages.
description: Revised arguments in section 7, results unchanged. 13 pages, 7 figures. Open-source software available at https://github.com/qutech/filter_functions
Nitrogen addition frequency and propagule pressure influence Solidago canadensis invasion into native plant community
Creators: name: Liu, Xuan-Shao
name: Cai, Jing-Fang
name: Liu, Lin
name: Sun, Kai
name: Jiang, Fan
name: Shen, Yi-Luan
name: A, Si-Ha
name: Li, Hong-Li
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Ecology
subject: FOS: Biological sciences
subject: Marine Biology
subject: Plant Biology

description: Propagule pressure (i.e., the number of propagules) has long been recognized to play an essential role in plant invasion. But it is not clear whether propagule pressure influences the invasion of exotic plants into native plant communities when different frequencies of nitrogen are added. We established an experiment with three plant communities that included native plant communities alone (four grasses, two legumes and two forbs) or native plant communities with one or five invasive plants, Solidago canadensis, under three frequencies of nitrogen addition (no addition or low or high addition with the same amount). High propagule pressure significantly enhanced the biomass and relative dominance index of S. canadensis. Moreover, high propagule pressure only decreased the total and aboveground biomass of the legumes. However, the competitive effect between S. canadensis and the native community and biomass of the whole native community varied according to different frequencies. Overall, high propagule pressure encouraged invasion by S. canadensis, while alow nitrogen frequency was advantageous for the native community to resist invasion in this experiment. The results provide a scientific basis to manage and control the invasion of S. canadensis.
The Hubbard Model
Creators: name: Arovas, Daniel P.
name: Berg, Erez
name: Kivelson, Steven
name: Raghu, Srinivas
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The repulsive Hubbard model has been immensely useful in understanding strongly correlated electron systems, and serves as the paradigmatic model of the field. Despite its simplicity, it exhibits a strikingly rich phenomenology which is reminiscent of that observed in quantum materials. Nevertheless, much of its phase diagram remains controversial. Here, we review a subset of what is known about the Hubbard model, based on exact results or controlled approximate solutions in various limits, for which there is a suitable small parameter. Our primary focus is on the ground state properties of the system on various lattices in two spatial dimensions, although both lower and higher dimensions are discussed as well. Finally, we highlight some of the important outstanding open questions.
description: To appear in Annual Reviews of Condensed Matter Physics
Generic instability of the dynamics underlying the Belinski-Khalatnikov-Lifshitz scenario
Creators: name: Goldstein, Piotr
name: Piechocki, Włodzimierz
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: A class of exact solutions to the Belinski-Khalatnikov-Lifshitz (BKL) scenario is derived and tested for their stability against small perturbations. These are the only regular solutions in the Painlevé sense. We prove that they are unstable in the vicinity of the cosmological singularity. Regularity of the dynamics is also examined with the dynamical systems method. Our results confirm the conjecture of BKL that the dynamics near the singularity becomes generically chaotic.
description: 17 pages, 3 figures, version accepted for publication in EPJC
Cyclization of aromatic aldehydes and phenylenediamines under reduced pressure: A convenient, environmentally friendly, and simple procedure for benzimidazole precursors
Creators: name: Choltirosn Sutapin
name: Suwabun Chirachanchai
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Biochemistry
subject: Neuroscience
subject: Biotechnology
subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 111714 Mental Health
subject: FOS: Health sciences
subject: 110309 Infectious Diseases
subject: Computational Biology

description: The condensation of phenylenediamines with aromatic aldehydes in the presence of catalysts to obtain benzimidazoles under harsh condition is achieved by various reported conditions. The present work demonstrates a convenient, environmentally friendly, and simple procedure to obtain benzimidazoles through the cyclization between phenylenediamines and aromatic aldehydes under reduced pressure. By simply adding aromatic aldehydes to diaminobenzene derivatives and allowing the stoichiometric reaction at room temperature under reduced pressure at 66.6 Pa, the dehydrogenation leads to benzimidazoles with the yield as high as 80–90%. In addition, the purging of H2 gas to benzimidazoles results in the hydrogenation of imidazole to obtain the intermediate benzimidazolidine form. This confirms how the cyclization relies on the reduced pressure. This synthesis pathway not only gives the aromatic aldehydes with high yield under the mild condition but also the selection of benzaldehydes with reactive functional groups leads to the precursors for other chemical modifications and polymerizations.
Towards Prebiotic Chemistry on Titan: Impact experiments on organic haze particles
Creators: name: Pearce, Ben K. D.
name: Hörst, Sarah M.
name: Cline, Christopher J.
name: Cintala, Mark J.
name: He, Chao
name: Sebree, Joshua A.
name: MacKenzie, Shannon M.
name: Daly, R. Terik
name: Pontefract, Alexandra J.
name: Pesciotta, Cara
Publisher: name: arXiv
Year: 2024
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Biological Physics (physics.bio-ph)
subject: Chemical Physics (physics.chem-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Impacts are critical to producing the aqueous environments necessary to stimulate prebiotic chemistry on Titan's surface. Furthermore, organic hazes resting on the surface are a likely feedstock of biomolecules. In this work, we conduct impact experiments on laboratory-produced organic haze particles and haze/sand mixtures and analyze these samples for life's building blocks. Samples of unshocked haze and sand particles are also analyzed to determine the change in biomolecule concentrations and distributions from shocking. Across all samples, we detect seven nucleobases, nine proteinogenic amino acids, and five other biomolecules (e.g., urea) using a blank subtraction procedure to eliminate signals due to contamination. We find that shock pressures of 13 GPa variably degrade nucleobases, amino acids, and a few other organics in haze particles and haze/sand mixtures; however, certain individual biomolecules become enriched or are even produced from these events. Xanthine, threonine, and aspartic acid are enriched or produced in impact experiments containing sand, suggesting these minerals may catalyze the production of these biomolecules. On the other hand, thymine and isoleucine/norleucine are enriched or produced in haze samples containing no sand, suggesting catalytic grains are not necessary for all impact shock syntheses. Uracil, glycine, proline, cysteine, and tyrosine are the most unstable to impact-related processing. These experiments suggest that impacts alter biomolecule distributions on Titan's surface, and that organic hazes co-occurring with fine-grained material on the surface may provide an initial source for further prebiotic chemistry on Titan.
description: Accepted to PSJ. 13 pages, 3 tables, 7 figures
On Concavity of Solutions of the Nonlinear Poisson Equation
Creators: name: Steinerberger, Stefan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We consider the nonlinear Poisson equation $-Δu = f(u)$ in domains $Ω\subset \mathbb{R}^n$ with Dirichlet boundary conditions on $\partial Ω$. We show (for monotonically increasing concave $f$ with small Lipschitz constant) that if $D^2 u$ is negative semi-definite on the boundary, then $u$ is concave. A conjecture of Saint Venant from 1856 (proven by Polya in 1948) is that among all domains $Ω$ of fixed measure, the solution of $-Δu =1$ assumes its largest maximum when $Ω$ is a ball. We extend this to $-Δu =f(u)$ for monotonically increasing $f$ with small Lipschitz constant.
Computational DNA binding studies of (-)-epigallocatechin-3-gallate.
Creators: name: Galindo-Murillo, Rodrigo
name: Cheatham, Thomas E.
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: Cell Biology
subject: Molecular Biology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer

description: The catechin family of molecules that are present in the leaves of green tea have been under investigation since the anti-oxidant and anti-inflammatory properties of tea were discovered. Among multiple proposed therapeutic targets of these molecules, the direct interaction with nucleic acids have been proposed and experimentally observedbut without clear knowledge about the potential binding modes between these ligands and DNA. One of these catechin structures, (─)-epigallocatechin gallate (EGCG), has three aromatic rings that could interact with double stranded DNA via terminal base pair stacking, intercalation, or through groove binding. Using enhanced sampling techniques and molecular dynamics simulations, we have found a stable complex between the EGCG ligand and DNA through intercalation of the trihydroxybenzoate aromatic ring and an ApC step. Moreover, we have calculated the absorption spectra of four possible binding modes and compared these to absorption profiles reported in the literature, and explored the possible DNA sequence preference for the EGCG ligand to bind. Our results suggest that an intercalative mode of interaction through the major groove is possible between the EGCG ligands and DNA with apparently very little DNA sequence selectivity.
Dissipative stabilization of high-dimensional GHZ states for neutral atoms
Creators: name: Zhao, Yue
name: Yang, Yu-Qing
name: Li, Weibin
name: Shao, Xiao-Qiang
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: High-dimensional quantum entanglement characterizes the entanglement of quantum systems within a larger Hilbert space, introducing more intricate and complex correlations among the entangled particles' states. The high-dimensional Greenberger-Horne-Zeilinger (GHZ) state, symbolic of this type of entanglement, is of significant importance in various quantum information processing applications. This study proposes integrating a neutral atom platform with quantum reservoir engineering to generate a high-dimensional GHZ state deterministically. Leveraging the advantages of neutral atoms in a modified unconventional Rydberg pumping mechanism, combined with controlled dissipation, we achieve a three-dimensional GHZ state with a fidelity surpassing 99\% through multiple pump and dissipation cycles. This innovative approach paves the way for experimentally feasible, deterministic preparation of high-dimensional GHZ states in Rydberg atom systems, thereby advancing the capabilities of quantum information processing.
description: Accepted by Applied Physics Letters, 7 pages, 5 figures
Evidence for X-ray Emission in Excess to the Jet Afterglow Decay 3.5 yrs After the Binary Neutron Star Merger GW 170817: A New Emission Component
Creators: name: Hajela, A.
name: Margutti, R.
name: Bright, J. S.
name: Alexander, K. D.
name: Metzger, B. D.
name: Nedora, V.
name: Kathirgamaraju, A.
name: Margalit, B.
name: Radice, D.
name: Guidorzi, C.
name: Berger, E.
name: MacFadyen, A.
name: Giannios, D.
name: Chornock, R.
name: Heywood, I.
name: Sironi, L.
name: Gottlieb, O.
name: Coppejans, D.
name: Laskar, T.
name: Cendes, Y.
name: Duran, R. Barniol
name: Eftekhari, T.
name: Fong, W.
name: McDowell, A.
name: Nicholl, M.
name: Xie, X.
name: Zrake, J.
name: Bernuzzi, S.
name: Broekgaarden, F. S.
name: Kilpatrick, C. D.
name: Terreran, G.
name: Villar, V. A.
name: Blanchard, P. K.
name: Gomez, S.
name: Hosseinzadeh, G.
name: Matthews, D. J.
name: Rastinejad, J. C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: For the first $\sim3$ years after the binary neutron star merger event GW 170817 the radio and X-ray radiation has been dominated by emission from a structured relativistic off-axis jet propagating into a low-density medium with n $< 0.01\,\rm{cm^{-3}}$. We report on observational evidence for an excess of X-ray emission at $δt>900$ days after the merger. With $L_x\approx5\times 10^{38}\,\rm{erg\,s^{-1}}$ at 1234 days, the recently detected X-ray emission represents a $\ge 3.2\,σ$ (Gaussian equivalent) deviation from the universal post jet-break model that best fits the multi-wavelength afterglow at earlier times. In the context of JetFit afterglow models, current data represent a departure with statistical significance $\ge 3.1\,σ$, depending on the fireball collimation, with the most realistic models showing excesses at the level of $\ge 3.7\,σ$. A lack of detectable 3 GHz radio emission suggests a harder broad-band spectrum than the jet afterglow. These properties are consistent with the emergence of a new emission component such as synchrotron radiation from a mildly relativistic shock generated by the expanding merger ejecta, i.e. a kilonova afterglow. In this context, we present a set of ab-initio numerical-relativity BNS merger simulations that show that an X-ray excess supports the presence of a high-velocity tail in the merger ejecta, and argues against the prompt collapse of the merger remnant into a black hole. Radiation from accretion processes on the compact-object remnant represents a viable alternative. Neither a kilonova afterglow nor accretion-powered emission have been observed before, as detections of BNS mergers at this phase of evolution are unprecedented.
description: 30 pages, 13 figures, Accepted for publication in ApJL
Permutation invariant Gaussian 2-matrix models
Creators: name: Barnes, George
name: Padellaro, Adrian
name: Ramgoolam, Sanjaye
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We construct the general permutation invariant Gaussian 2-matrix model for matrices of arbitrary size $D$. The parameters of the model are given in terms of variables defined using the representation theory of the symmetric group $S_D$. A correspondence is established between the permutation invariant polynomial functions of the matrix variables (the observables of the model) and directed colored graphs, which sheds light on stability properties in the large $D$ counting of these invariants. The refined counting of the graphs is given in terms of double cosets involving permutation groups defined by the local structure of the graphs. Linear and quadratic observables are transformed to an $S_D$ representation theoretic basis and are used to define the convergent Gaussian measure. The perturbative rules for the computation of expectation values of graph-basis observables of any degree are given in terms of the representation theoretic parameters. Explicit results for a number of observables of degree up to four are given along with a Sage programme that computes general expectation values.
description: 80 pages, 11 figures
Does Your Dermatology Classifier Know What It Doesn't Know? Detecting the Long-Tail of Unseen Conditions
Creators: name: Roy, Abhijit Guha
name: Ren, Jie
name: Azizi, Shekoofeh
name: Loh, Aaron
name: Natarajan, Vivek
name: Mustafa, Basil
name: Pawlowski, Nick
name: Freyberg, Jan
name: Liu, Yuan
name: Beaver, Zach
name: Vo, Nam
name: Bui, Peggy
name: Winter, Samantha
name: MacWilliams, Patricia
name: Corrado, Greg S.
name: Telang, Umesh
name: Liu, Yun
name: Cemgil, Taylan
name: Karthikesalingam, Alan
name: Lakshminarayanan, Balaji
name: Winkens, Jim
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We develop and rigorously evaluate a deep learning based system that can accurately classify skin conditions while detecting rare conditions for which there is not enough data available for training a confident classifier. We frame this task as an out-of-distribution (OOD) detection problem. Our novel approach, hierarchical outlier detection (HOD) assigns multiple abstention classes for each training outlier class and jointly performs a coarse classification of inliers vs. outliers, along with fine-grained classification of the individual classes. We demonstrate the effectiveness of the HOD loss in conjunction with modern representation learning approaches (BiT, SimCLR, MICLe) and explore different ensembling strategies for further improving the results. We perform an extensive subgroup analysis over conditions of varying risk levels and different skin types to investigate how the OOD detection performance changes over each subgroup and demonstrate the gains of our framework in comparison to baselines. Finally, we introduce a cost metric to approximate downstream clinical impact. We use this cost metric to compare the proposed method against a baseline system, thereby making a stronger case for the overall system effectiveness in a real-world deployment scenario.
description: Under Review, 19 Pages
Strong-field response time and its implications on attosecond measurement
Creators: name: Chen, Chao
name: Che, Jiayin
name: Wang, Shang
name: Xin, Guoguo
name: Chen, Yanjun
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phenomena and processes and raises a series of questions of concepts, theories and methods. Recent studies show that the Coulomb potential can cause the ionization time lag (about 100 attoseconds) between instants of the field maximum and the ionization-rate maximum. This lag can be understood as the response time of the electronic wave function to the strong-field-induced ionization event. It has a profound influence on the subsequent ultrafast dynamics of the ionized electron and can significantly change the time-frequency properties of electron trajectory (an important theoretical tool for attosecond measurement). Here, the research progress of response time and its implications on attosecond measurement are briefly introduced.
description: 7 pages, 3 figures
Unlimited non-causal correlations and their relation to non-locality
Creators: name: Baumeler, Ämin
name: Gilani, Amin Shiraz
name: Rashid, Jibran
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Non-causal correlations certify the lack of a definite causal order among localized space-time regions. In stark contrast to scenarios where a single region influences its own causal past, some processes that distribute non-causal correlations satisfy a series of natural desiderata: logical consistency, linear and reversible dynamics, and computational tameness. Here, we present such processes among arbitrary many regions where each region influences every other but itself, and show that the above desiderata are altogether insufficient to limit the amount of "acausality" of non-causal correlations. This leaves open the identification of a principle that forbids non-causal correlations. Our results exhibit qualitative and quantitative parallels with the non-local correlations due to Ardehali and Svetlichny.
description: 14 + 4 pages appendix, 6 figures, 1 table, final version
State and Topology Estimation for Unobservable Distribution Systems using Deep Neural Networks
Creators: name: Azimian, Behrouz
name: Biswas, Reetam Sen
name: Moshtagh, Shiva
name: Pal, Anamitra
name: Tong, Lang
name: Dasarathy, Gautam
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Time-synchronized state estimation for reconfigurable distribution networks is challenging because of limited real-time observability. This paper addresses this challenge by formulating a deep learning (DL)-based approach for topology identification (TI) and unbalanced three-phase distribution system state estimation (DSSE). Two deep neural networks (DNNs) are trained for time-synchronized DNN-based TI and DSSE, respectively, for systems that are incompletely observed by synchrophasor measurement devices (SMDs) in real-time. A data-driven approach for judicious SMD placement to facilitate reliable TI and DSSE is also provided. Robustness of the proposed methodology is demonstrated by considering non-Gaussian noise in the SMD measurements. A comparison of the DNN-based DSSE with more conventional approaches indicates that the DL-based approach gives better accuracy with smaller number of SMDs.
description: 13 pages. arXiv admin note: substantial text overlap with arXiv:2011.04272
Highly efficient and green esterification of carboxylic acids in deep eutectic solvents without any other additives
Creators: name: Sumera Yasmin
name: Sheng, Wen-Bing
name: Peng, Cai-Yun
name: Atta-Ur Rahman
name: Duan-Fang Liao
name: M. Iqbal Choudhary
name: Wanga, Wei
Publisher: name: Taylor & Francis
Year: 2017
Subjects: subject: Biochemistry
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Plant Biology

description: A protocol that carboxylic acids esterifies with the quaternary ammonium salt of deep eutectic solvent (DES) is presented, which opens a new access to ester using DES as alkylating agent, solvent, and catalyst. The reaction runs smoothly in DES without any other additives. Substituted cinnamic acids, aromatic acids, and aliphatic acids can be esterified in moderate to good yields. The advantages of this reaction include excellent functional group compatibility and simple reaction procedure.