cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Spin tunneling and topological selection rules for integer spins
Creators: name: Leuenberger, Michael N.
name: Loss, Daniel
Publisher: name: arXiv
Year: 2000
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present topological interference effects for the tunneling of a single large spin, which are caused by the symmetry of a general class of magnetic anisotropies. The interference originates from spin Berry phases associated with different tunneling paths exposed to the same dynamics. Introducing a generalized path integral for coherent spin states, we evaluate transition amplitudes between ground as well as low-lying excited states. We show that these interference effects lead to topological selection rules and spin-parity effects for integer spins that agree with quantum selection rules and which thus provide a generalization of the Kramers degeneracy to integer spins. Our results apply to the molecular magnets Mn12 and Fe8.
description: 4 pages, 3 EPS figures, REVTeX
Novel mechanism of photoinduced reversible phase transitions in molecule-based magnets
Creators: name: Kawamoto, Tohru
name: Asai, Yoshihiro
name: Abe, Shuji
Publisher: name: arXiv
Year: 2000
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A novel microscopic mechanism of bi-directional structural changes is proposed for the photo-induced magnetic phase transition in Co-Fe Prussian blue analogues on the basis of ab initio quantum chemical cluster calculations. It is shown that the local potential energies of various spin states of Co are sensitive to the number of nearest neighbor Fe vacancies. As a result, the forward and backward structural changes are most readily initiated by excitation of different local regions by different photons. This mechanism suggests an effective strategy to realize photoinduced reversible phase transitions in a general system consisting of two local components.
description: 4 pages, LaTex, 3 figures, to appear in Phys. Rev. Lett
Geometrically Enhanced Thermoelectric Effects in Graphene Nanoconstrictions
Creators: name: Harzheim, Achim
name: Spiece, Jean
name: Evangeli, Charalambos
name: McCann, Edward
name: Falko, Vladimir
name: Sheng, Yuewen
name: Warner, Jamie H.
name: Briggs, G. Andrew D.
name: Mol, Jan A.
name: Gehring, Pascal
name: Kolosov, Oleg V.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The influence of nanostructuring and quantum confinement on the thermoelectric properties of materials has been extensively studied. While this has made possible multiple breakthroughs in the achievable figure of merit, classical confinement, and its effect on the local Seebeck coefficient has mostly been neglected, as has the Peltier effect in general due to the complexity of measuring small temperature gradients locally. Here we report that reducing the width of a graphene channel to 100 nm changes the Seebeck coefficient by orders of magnitude. Using a scanning thermal microscope allows us to probe the local temperature of electrically contacted graphene two-terminal devices or to locally heat the sample. We show that constrictions in mono- and bilayer graphene facilitate a spatially correlated gradient in the Seebeck and Peltier coefficient, as evidenced by the pronounced thermovoltage $V_{th}$ and heating/cooling response $ΔT_{Peltier}$, respectively. This geometry dependent effect, which has not been reported previously in 2D materials, has important implications for measurements of patterned nanostructures in graphene and points to novel solutions for effective thermal management in electronic graphene devices or concepts for single material thermocouples.
Charming Top Decays with Flavor Changing Neutral Higgs Boson and WW at Hadron Colliders
Creators: name: Jain, Rishabh
name: Kao, Chung
Publisher: name: arXiv
Year: 2019
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the prospects for discovering a top quark decaying into one light Higgs boson ($h^0$) along with a charm quark ($c$) in top quark pair production at the CERN Large Hadron Collider (LHC) and future hadron colliers. A general two Higgs doublet model is adopted to study the signature of flavor changing neutral Higgs (FCNH) interactions with $t \to c h^0$, followed by $h^0 \to WW^* \to \ell^+ \ell^- +\notE_T$, where $h^0$ is the CP-even Higgs boson and $\notE_T$ stands for missing transverse energy from neutrinos. We study the discovery potential for this FCNH signal and physics background from dominant processes with realistic acceptance cuts as well as tagging and mistagging efficiencies. Promising results are found for the LHC running at 13 TeV and 14 TeV center-of-mass energy as well as future pp colliders at 27 TeV and 100 TeV.
description: 15 pages, 7 figures, version to appear in Physical Review D. arXiv admin note: text overlap with arXiv:1112.1707
Methylation of H3-Lysine 79 Is Mediated by a New Family of HMTases without a SET Domain
Creators: name: Feng, Qin
name: Tempst, Paul
name: Struhl, Kevin
name: Ng, Huck Hui
name: Wang, Hengbin
name: Zhang, Yi
name: Erdjument-Bromage, Hediye
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2002

description: AbstractThe N-terminal tails of core histones are subjected to multiple covalent modifications, including acetylation, methylation, and phosphorylation [1]. Similar to acetylation, histone methylation has emerged as an important player in regulating chromatin dynamics and gene activity [2–4]. Histone methylation occurs on arginine and lysine residues and is catalyzed by two families of proteins, the protein arginine methyltransferase family and the SET-domain-containing methyltransferase family [3]. Here, we report that lysine 79 (K79) of H3, located in the globular domain, can be methylated. K79 methylation occurs in a variety of organisms ranging from yeast to human. In budding yeast, K79 methylation is mediated by the silencing protein DOT1. Consistent with conservation of K79 methylation, DOT1 homologs can be found in a variety of eukaryotic organisms. We identified a human DOT1-like (DOT1L) protein and demonstrated that this protein possesses intrinsic H3-K79-specific histone methyltransferase (HMTase) activity in vitro and in vivo. Furthermore, we found that K79 methylation level is regulated throughout the cell cycle. Thus, our studies reveal a new methylation site and define a novel family of histone lysine methyltransferase.
Bio-inspired method based on bone architecture to optimize the structure of mechanical workspieces
Creators: name: Audibert, Clement
name: Chaves-Jacob, Julien
name: Linares, Jean-Marc
name: Lopez, Quentin-Alexis
Publisher: name: arXiv
Year: 2018
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Nowadays, additive manufacturing processes greatly simplify the production of openwork workpiece providing new opportunities for workpieces design. Based on Nature knowledge, a new bio-inspired workpiece structural optimization approach is presented in this paper. This approach is derived from bones structure. The aim of this method is to reduce the workpiece weight maintaining an acceptable resistance. Like in bones, the porosity of the part to optimize was controlled by a bio-inspired method as function of the local stress field. Shape, size and orientation of the porosities were derived from bone structure; two main strategies were used: one inspired of avian species and other inspired of terrestrial mammalian. Subsequently, to validate this method, an experimental test was carried out for comparing a topological optimization and the proposed bio-inspired designs. This test was conducted on a beam part in 2.5D subjected to a static three-point bending with 65% of density. Three beams were manufactured by 3D metal printing: two bio-inspired beams (terrestrial mammalian and avian species) and the last designed using a topological optimization method. Experimental test results demonstrated the usefulness of the proposed method. This bio-inspired structural optimization approach opens up new prospects in design of openwork workpiece.
Purification and Functional Characterization of SET8, a Nucleosomal Histone H4-Lysine 20-Specific Methyltransferase
Creators: name: Erdjument-Bromage, Hediye
name: Zhang, Yi
name: Fang, Jia
name: Simon, Jeffrey A.
name: Feng, Qin
name: Xia, Li
name: Ketel, Carrie S.
name: Wang, Hengbin
name: Cao, Ru
name: Tempst, Paul
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2002

description: AbstractBackground: Covalent modifications of histone N-terminal tails play fundamental roles in regulating chromatin structure and function. Extensive studies have established that acetylation of specific lysine residues in the histone tails plays an important role in transcriptional regulation. Besides acetylation, recent studies have revealed that histone methylation also has significant effects on heterochromatin formation and transcriptional regulation. Histone methylation occurs on specific arginine and lysine residues of histones H3 and H4. Thus far, only 2 residues on histone H4 are known to be methylated. While H4-arginine 3 (H4-R3) methylation is mediated by PRMT1, the enzyme(s) responsible for H4-lysine 20 (H4-K20) methylation is not known.Results: To gain insight into the function of H4-K20 methylation, we set out to identify the enzyme responsible for this modification. We purified and cloned a novel human SET domain-containing protein, named SET8, which specifically methylates H4 at K20. SET8 is a single subunit enzyme and prefers nucleosomal substrates. We find that H4-K20 methylation occurs in a wide range of higher eukaryotic organisms and that SET8 homologs exist in C. elegans and Drosophila. We demonstrate that the Drosophila SET8 homolog has the same substrate specificity as its human counterpart. Importantly, disruption of SET8 in Drosophila reduces levels of H4-K20 methylation in vivo and results in lethality. Although H4-K20 methylation does not correlate with gene activity, it appears to be regulated during the cell cycle.Conclusions: We identified and characterized an evolutionarily conserved nucleosomal H4-K20-specific methyltransferase and demonstrated its essential role in Drosophila development.
Fermions in spherical field theory
Creators: name: Lee, Dean
Publisher: name: arXiv
Year: 1998
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Condensed Matter (cond-mat)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We derive the spherical field formalism for fermions. We find that the spherical field method is free from certain difficulties which complicate lattice calculations, such as fermion doubling, missing axial anomalies, and computational problems regarding internal fermion loops.
description: corrected journal info
A modified cross-entropy algorithm for multiple change-point detection
Creators: name: Lie, Eric Chandra
Publisher: name: Macquarie University
Year: 2024
Subjects: classificationCode: 490503
subject: Computational statistics

description: In a long data sequence, abrupt variations may occur at different locations, dividing the sequence to multiple smaller segments. These abrupt changes may represent the sudden changes in the underlying parameters of a statistical model of the sequence. The problem of detecting these events are typically known as a change-point problem. Change-point problems arise in many different fields including biology (e.g DNA segmentation), financial analysis (e.g stock volatility) and sensor data (e.g pedestrian foot traffic during different times of the year). One method to approach the change-point problem is to apply the Cross-Entropy algorithm, which is a model based evolutionary optimization algorithm. Commonly, the underlying (or sampling) distribution used for the Cross-Entropy algorithm is Gaussian distribution or Beta distribution, which draw samples from an approximate space of the change-point model. This thesis focuses on using the Dirichlet distribution as the underlying distribution, which samples from the exact space of the parameters of change-point model. We compare the accuracy of the proposed algorithm using artificially generated sequences and subsequently apply the method to a real pedestrian sensor data to illustrate the utility of this approach.
Additional file 1 of Universal immunotherapeutic strategy for hepatocellular carcinoma with exosome vaccines that engage adaptive and innate immune responses
Creators: name: Zuo, Bingfeng
name: Zhang, Yang
name: Zhao, Kangjie
name: Wu, Li
name: Qi, Han
name: Yang, Rong
name: Gao, Xianjun
name: Geng, Mengyuan
name: Wu, Yingjie
name: Jing, Renwei
name: Zhou, Qibing
name: Seow, Yiqi
name: Yin, HaiFang
Publisher: name: figshare
Year: 2022
Subjects: subject: Immunology
subject: FOS: Clinical medicine

description: Additonal file 1. Supplementary Figures.
Additional file 1: of The immune suppressive microenvironment of human gliomas depends on the accumulation of bone marrow-derived macrophages in the center of the lesion
Creators: name: Pinton, Laura
name: Masetto, Elena
name: Vettore, Marina
name: Solito, Samantha
name: Magri, Sara
name: DâAndolfi, Marta
name: Bianco, Paola
name: Lollo, Giovanna
name: Benoit, Jean-Pierre
name: Hideho Okada
name: Diaz, Aaron
name: Puppa, Alessandro
name: Mandruzzato, Susanna
Publisher: name: figshare
Year: 2019
Subjects: subject: Space Science
subject: Medicine
subject: Cell Biology
subject: Molecular Biology
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer

description: Table S1. Cell populations analyzed in tumor tissues of glioma patients. Supplementary materials and methods. Description of patient characteristics, multiparametric flow cytometry, functional assay, t-SNE analysis and experiments with nanoparticles. (DOCX 22 kb)
Breakdown of the Wiedemann-Franz law in AB-stacked bilayer graphene
Creators: name: Zarenia, Mohammad
name: Vignale, Giovanni
name: Smith, Thomas Benjamin
name: Principi, Alessandro
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a simple theory of thermoelectric transport in bilayer graphene and report our results for the electrical resistivity, the thermal resistivity, the Seebeck coefficient, and the Wiedemann-Franz ratio as functions of doping density and temperature. In the absence of disorder, the thermal resistivity tends to zero as the charge neutrality point is approached; the electric resistivity jumps from zero to an intrinsic finite value, and the Seebeck coefficient diverges in the same limit. Even though these results are similar to those obtained for single-layer graphene, their derivation is considerably more delicate. The singularities are removed by the inclusion of a small amount of disorder, which leads to the appearance of a "window" of doping densities $0
description: 5 pages, 2 figures. arXiv admin note: text overlap with arXiv:1811.08914
Influence of nonlocal electrodynamics on the anisotropic vortex pinning in $YNi_2B_2C$
Creators: name: Silhanek, A. V.
name: Thompson, J. R.
name: Civale, L.
name: Paul, D. McK.
name: Tomy, C. V.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We have studied the pinning force density Fp of YNi_2B_2C superconductors for various field orientations. We observe anisotropies both between the c-axis and the basal plane and within the plane, that cannot be explained by usual mass anisotropy. For magnetic field $H \parallel c$, the reorientation structural transition in the vortex lattice due to nonlocality, which occurs at a field $H_1 \sim 1kOe$, manifests itself as a kink in Fp(H). When $H \bot c$, Fp is much larger and has a quite different H dependence, indicating that other pinning mechanisms are present. In this case the signature of nonlocal effects is the presence of a fourfold periodicity of Fp within the basal plane.
description: 4 pages, 3 figures
Vortices with antiferromagnetic cores in the SO(5) theory of high temperature superconductivity
Creators: name: Alama, S.
name: Berlinsky, A. J.
name: Bronsard, L.
name: Giorgi, T.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We consider the problem of superconducting Ginzburg-Landau (G-L) vortices with antiferromagnetic cores which arise in Zhang's SO(5) model of antiferromagnetism (AF) and high temperature superconductivity (SC). This problem was previously considered by Arovas et al. who constructed approximate "variational" solutions, in the large kappa limit, to estimate the domain of stability of such vortices in the temperature-chemical potential phase diagram. By solving the G-L equations numerically for general kappa, we show that the amplitude of the antiferromagnetic component at the vortex core decreases to zero continuously at a critical value of the AF-SC anisotropy (g~0.25) which is essentially independent of kappa for large kappa. The magnetic field profile, the vortex line energy and the value of the B-field at the center of the vortex core, as functions of anisotropy are also presented.
description: 8 pages
PAR Proteins Regulate Microtubule Dynamics at the Cell Cortex in C. elegans
Creators: name: Goldstein, Bob
name: Maddox, Paul S.
name: Labbé, Jean-Claude
name: Salmon, E.D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2003

description: BACKGROUND: The PAR proteins are known to be localized asymmetrically in polarized C. elegans, Drosophila, and human cells and to participate in several cellular processes, including asymmetric cell division and spindle orientation. Although astral microtubules are known to play roles in these processes, their behavior during these events remains poorly understood.

RESULTS: We have developed a method that makes it possible to examine the residence time of individual astral microtubules at the cell cortex of developing embryos. Using this method, we found that microtubules are more dynamic at the posterior cortex of the C. elegans embryo compared to the anterior cortex during spindle displacement. We further observed that this asymmetry depends on the PAR-3 protein and heterotrimeric G protein signaling, and that the PAR-2 protein affects microtubule dynamics by restricting PAR-3 activity to the anterior of the embryo.

CONCLUSIONS: These results indicate that PAR proteins function to regulate microtubule dynamics at the cortex during microtubule-dependent cellular processes.
Dynamical signatures of topological order in the driven-dissipative Kitaev chain
Creators: name: van Caspel, Moos
name: Arze, Sergio Enrique Tapias
name: Castillo, Isaac Pérez
Publisher: name: arXiv
Year: 2018
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate the effects of dissipation and driving on topological order in superconducting nanowires. Rather than studying the non-equilibrium steady state, we propose a method to classify and detect dynamical signatures of topological order in open quantum systems. Bulk winding numbers for the Lindblad generator $\hat{\mathcal{L}}$ of the dissipative Kitaev chain are found to be linked to the presence of Majorana edge master modes -- localized eigenmodes of $\hat{\mathcal{L}}$. Despite decaying in time, these modes provide dynamical fingerprints of the topological phases of the closed system, which are now separated by intermediate regions where winding numbers are ill-defined and the bulk-boundary correspondence breaks down. Combining these techniques with the Floquet formalism reveals higher winding numbers and different types of edge modes under periodic driving. Finally, we link the presence of edge modes to a steady state current.
description: Submission to SciPost. 29 pages, 8 figures
Rnd Proteins Function as RhoA Antagonists by Activating p190 RhoGAP
Creators: name: Burridge, Keith
name: Der, Channing J
name: Wennerberg, Krister
name: Hansen, Steen H
name: Ellerbroek, Shawn M
name: Forget, Marie-Annick
name: Arthur, William T
name: Settleman, Jeffrey
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2003

description: AbstractBackground: The Rnd proteins Rnd1, Rnd2, and Rnd3 (RhoE) comprise a unique branch of Rho-family G-proteins that lack intrinsic GTPase activity and consequently remain constitutively "active." Prior studies have suggested that Rnd proteins play pivotal roles in cell regulation by counteracting the biological functions of the RhoA GTPase, but the molecular basis for this antagonism is unknown. Possible mechanisms by which Rnd proteins could function as RhoA antagonists include sequestration of RhoA effector molecules, inhibition of guanine nucleotide exchange factors, and activation of GTPase-activating proteins (GAPs) for RhoA. However, effector molecules of Rnd proteins with such properties have not been identified.Results: Here we identify p190 RhoGAP (p190), the most abundant GAP for RhoA in cells, as an interactor with Rnd proteins and show that this interaction is mediated by a p190 region that is distinct from the GAP domain. Using Rnd3-RhoA chimeras and Rnd3 mutants defective in p190 binding, as well as p190-deficient cells, we demonstrate that the cellular effects of Rnd expression are mediated by p190. We moreover show that Rnd proteins increase the GAP activity of p190 toward GTP bound RhoA and, finally, demonstrate that expression of Rnd3 leads to reduced cellular levels of RhoA-GTP by a p190-dependent mechanism.Conclusions: Our results identify p190 RhoGAPs as effectors of Rnd proteins and demonstrate a novel mechanism by which Rnd proteins function as antagonists of RhoA.
Alley cropping systems: key objectives - Sistemas de culturas nas entrelinhas: objetivos principais
Creators: name: Lerberghe, Philippe Van
Publisher: name: Zenodo
Year: 2017
Subjects: ecossystem services
shelter
soil erosion
hardwood trees
hight quality timber
poplar
fast growing species
water quality
sustainability
serviços do ecossistema
abrigo
erosão do solo
folhosas
madeira de alta qualidade
choupo
espécies de crescimento rápido

description: Tradução de leaflet do projeto AGFORWARD - Num sistema de culturas nas entrelinhas as árvores são multifuncionais, com o objetivo de fornecer, a par da madeira e de frutos, uma multiplicidade de serviços ao ecossistema. Estes incluem o abrigo para as culturas, o favorecimento de organismos benéficos para o hospedeiro, o aumento da fertilidade do solo e do sequestro de carbono, a mitigação dos efeitos das alterações climáticas e a proteção contra a erosão do solo. Este tipo de sistemas agroflorestais visa o aumento da produtividade e da rentabilidade da exploração, promovendo o desenvolvimento de paisagens resilientes. O desenvolvimento de sistemas de cultura nas entrelinhas necessita de uma conceção cuidadosa em termos das motivações e dos constrangimentos da sua adoção, considerando criteriosamente os objetivos a atingir e as informações necessárias para obter sucesso. A introdução de árvores em sistemas agrícolas ocasiona a alteração do uso da terra a longo prazo (normalmente entre 20 e 80 anos). Deve-se ter cuidado em assegurar que o diagnóstico inicial e o planeamento técnico sejam apropriados para assegurar o sucesso.
Stable Vortex Configurations in a Cylinder
Creators: name: Zieve, R. J.
name: Donev, L. A. K.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Condensed Matter (cond-mat)
subject: FOS: Physical sciences

description: We calculate stable arrangements for a single superfluid vortex pinned to the wall of a stationary cylindrical container. We find that, independent of the details of the pinning site, stable vortices must subtend most of the cell horizontally and cannot be vertical or nearly vertical. More generally, the geometry of a container severely limits the possible vortex configurations, making macroscopic trapped vortices less common than previously believed.
description: 2 new figures with substantial discussion; 9 pages, 12 figures total; to appear in J. Low Temp. Phys
Identifying the protein folding nucleus using molecular dynamics
Creators: name: Dokholyan, Nikolay V.
name: Buldyrev, Sergey V.
name: Stanley, H. Eugene
name: Shakhnovich, Eugene I.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantitative Biology (q-bio)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Molecular dynamics simulations of folding in an off-lattice protein model reveal a nucleation scenario, in which a few well-defined contacts are formed with high probability in the transition state ensemble of conformations. Their appearance determines folding cooperativity and drives the model protein into its folded conformation.
description: 6 pages including 7 figures
Additional file 3: of Characterization of a dominant mutation for the liguleless trait: Aegilops tauschii liguleless (Lgt)
Creators: name: Dresvyannikova, Alina
name: Watanabe, Nobuyoshi
name: Muterko, Alexander
name: Krasnikov, Alexander
name: Goncharov, Nikolay
name: Dobrovolskaya, Oxana
Publisher: name: figshare
Year: 2019
Subjects: subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Evolutionary Biology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Plant Biology

description: Table S1. List of DArTseq-derived SNPs. (DOCX 145 kb)
C. elegans PAR Proteins Function by Mobilizing and Stabilizing Asymmetrically Localized Protein Complexes
Creators: name: Goldstein, Bob
name: Canman, Julie C
name: Meyer, Nicole
name: Cheeks, Rebecca J
name: Strome, Susan
name: Gabriel, Willow N
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2004

description: AbstractBackground: The PAR proteins are part of an ancient and widely conserved machinery for polarizing cells during animal development. Here we use a combination of genetics and live imaging methods in the model organism Caenorhabditis elegans to dissect the cellular mechanisms by which PAR proteins polarize cells.Results: We demonstrate two distinct mechanisms by which PAR proteins polarize the C. elegans zygote. First, we show that several components of the PAR pathway function in intracellular motility, producing a polarized movement of the cell cortex. We present evidence that this cortical motility may drive the movement of cellular components that must become asymmetrically distributed, including both germline-specific ribonucleoprotein complexes and cortical domains containing the PAR proteins themselves. Second, PAR-1 functions to refine the asymmetric localization of germline ribonucleoprotein complexes by selectively stabilizing only those complexes that reach the PAR-1-enriched posterior cell cortex during the period of cortical motility.Conclusions: These results identify two cellular mechanisms by which the PAR proteins polarize the C. elegans zygote, and they suggest mechanisms by which PAR proteins may polarize cells in diverse animal systems.
Signaling Interplay in Ras Superfamily Function
Creators: name: Mitin, Natalia
name: Der, Channing J.
name: Rossman, Kent L.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2005

description: Ras proteins function as signaling hubs that are activated by convergent signaling pathways initiated by extracellular stimuli. Activated Ras in turn regulates a diversity of downstream cytoplasmic signaling cascades. Ras proteins are founding members of a large superfamily of small GTPases that have significant sequence and biochemical similarities. Recent observations have established a complex signaling interplay between Ras and other members of the family. A key biochemical mechanism facilitating this crosstalk involves guanine nucleotide exchange factors (GEFs), which serve as regulators and effectors, as well as signaling integrators, of Ras signaling.
BО'LАJАK INFОRMАTIKА О'QITUVСHILАRIYBYU INFORMATIKA O'QITUVCHISINING KASBIY FAOLIYATI MAZMUNI
Creators: name: Muxlisov, Sodiqjon
Publisher: name: Zenodo
Year: 2024

description: Ushbu maqoladi oliy ta’lim bilan qamrov darajasini oshirish, xalqaro standartlar asosida yuqori malakali, kreativ va tizimli fikrlaydigan, mustaqil qaror qabul qila oladigan kadrlar tayyorlash, bo‘lajak informatika o‘qituvshilarining tashkiliy-pedagogik kompetentligini rivojlantirish, informatika o‘qituvshisining kasbiy tayyorgarligi mazmuni,  bo‘lajak pedagoglarda nafaqat fanga doir kompetensiyalarni, balki tashkiliy-pedagogik kompetentlikni tarkib toptirish, pedagoglarda kasbiy tajriba ta’sirida takomillashtiriladigan komponentlar haqida nazariy ma’lumotlar yoritilgan va pedagogik tavsiyalar bayon etilgan.
The Mad1/Mad2 Complex as a Template for Mad2 Activation in the Spindle Assembly Checkpoint
Creators: name: Sala, Valeria
name: Sironi, Lucia
name: Nezi, Luigi
name: Musacchio, Andrea
name: Canman, Julie C.
name: Cimini, Daniela
name: Mapelli, Marina
name: Faretta, Mario
name: Pearson, Chad G.
name: De Antoni, Anna
name: Salmon, Edward D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2005

description: AbstractBackground: The spindle assembly checkpoint (SAC) imparts fidelity to chromosome segregation by delaying anaphase until all sister chromatid pairs have become bipolarly attached. Mad2 is a component of the SAC effector complex that sequesters Cdc20 to halt anaphase. In prometaphase, Mad2 is recruited to kinetochores with the help of Mad1, and it is activated to bind Cdc20. These events are linked to the existence of two distinct conformers of Mad2: a closed conformer bound to its kinetochore receptor Mad1 or its target in the checkpoint Cdc20 and an open conformer unbound to these ligands.Results: We investigated the mechanism of Mad2 recruitment to the kinetochore during checkpoint activation and subsequent transfer to Cdc20. We report that a closed conformer of Mad2 constitutively bound to Mad1, rather than Mad1 itself, is the kinetochore receptor for cytosolic open Mad2 and show that the interaction of open and closed Mad2 conformers is essential to sustain the SAC.Conclusions: We propose that closed Mad2 bound to Mad1 represents a template for the conversion of open Mad2 into closed Mad2 bound to Cdc20. This simple model, which we have named the "Mad2 template" model, predicts a mechanism for cytosolic propagation of the spindle checkpoint signal away from kinetochores.
Absence of non-linear Meissner effect in YBa2Cu3O6.95
Creators: name: Carrington, A.
name: Giannetta, R. W.
name: Kim, J. T.
name: Giapintzakis, J.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We present measurements the field and temperature dependence of the penetration depth (lambda) in high purity, untwinned single crystals of YBa2Cu3O6.95 in all three crystallographic directions. The temperature dependence of lambda is linear down to low temperatures, showing that our crystals are extremely clean. Both the magnitude and temperature dependence of the field dependent correction to lambda however, are considerably different from that predicted from the theory of the non-linear Meissner effect for a d-wave superconductor (Yip-Sauls theory). Our results suggest that the Yip-Sauls effect is either absent or is unobservably small in the Meissner state of YBa2Cu3O6.95.
description: 4 pages, 4 figures (Latex file + Postscipt figures)
A Bosonic Model of Hole Pairs
Creators: name: Siller, Th.
name: Troyer, M.
name: Rice, T. M.
name: White, S. R.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Condensed Matter (cond-mat)
subject: FOS: Physical sciences

description: We numerically investigate a bosonic representation for hole pairs on a two-leg t-J ladder where hard core bosons on a chain represent the hole pairs on the ladder. The interaction between hole pairs is obtained by fitting the density profile obtained with the effective model to the one obtained with the \tj model, taking into account the inner structure of the hole pair given by the hole-hole correlation function. For these interactions we calculate the Luttinger liquid parameter, which takes the universal value $K_ρ=1$ as half filling is approached, for values of the rung exchange $J'$ between strong coupling and the isotropic case. The long distance behavior of the hole-hole correlation function is also investigated. Starting from large $J'$, the correlation length first increases as expected, but diminishes significantly as $J'$ is reduced and bound holes sit mainly on adjacent rungs. As the isotropic case is approached, the correlation length increases again. This effect is related to the different kind of bonds in the region between the two holes of a hole pair when they move apart.
description: 11 pages
The Bias and Uncertainty of Redundant and Sky-Based Calibration under Realistic Sky and Telescope Conditions
Creators: name: Joseph, Ronniy C.
name: Trott, Cathryn M.
name: Wayth, Randall B.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The advent of a new generation of low frequency interferometers has opened a direct window into the Epoch of Reionisation (EoR). However, key to a detection of the faint 21-cm signal, and reaching the sensitivity limits of these arrays, is a detailed understanding of the instruments and their calibration. In this work we use simulations to investigate the bias and uncertainty of redundancy based calibration. Specifically, we study the influence of the flux distribution of the radio sky and the impact of antenna position offsets on the complex calibration solutions. We find that the position offsets introduce a bias into the phase component of the calibration solutions. This phase bias increases with the distance between bright radio sources and the pointing center, and with the flux density of these sources. This is potentially problematic for redundant calibration on MWA observations of EoR fields 1 and 2. EoR field 0, however, lacks such sources. We also compared the simulations with theoretical estimates for the bias and uncertainty in sky model based calibration on incomplete sky models for the redundant antenna tiles in the MWA. Our results indicate that redundant calibration outperforms sky based calibration due to the high positional precision of the MWA antenna tiles.
description: 15 pages, 10 figures, Accepted for publication in the Astronomical Journal
Supersymmetric Field Theory of Non-Equilibrium Thermodynamic System
Creators: name: Olemskoi, Alexander I.
name: Brazhnyi, Valerii A.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: On the basis of Langevin equation the optimal SUSY field scheme is formulated to discribe a non-equilibrium thermodynamic system with quenched disorder and non-ergodicity effects. Thermodynamic and isothermal susceptibilities, memory parameter and irreversible response are determined at different temperatures and quenched disorder intensities.
description: 35 pages, 6 figs, 2 diagrams, submitted to Physica A
The Murine Polycomb Group Protein Eed Is Required for Global Histone H3 Lysine-27 Methylation
Creators: name: Magnuson, Terry
name: Kalantry, Sundeep
name: Chamberlain, Stormy J.
name: Otte, Arie P.
name: Chen, Andrew
name: Yee, Della
name: Montgomery, Nathan D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2005

description: PcG proteins mediate heritable transcriptional silencing by generating and recognizing covalent histone modifications. One conserved PcG complex, PRC2, is composed of several proteins including the histone methyltransferase (HMTase) Ezh2, the WD-repeat protein Eed, and the Zn-finger protein Suz12. Ezh2 methylates histone H3 on lysine 27 (H3K27) [1, 2, 3 and 4], which serves as an epigenetic mark mediating silencing. H3K27 can be mono-, di-, or trimethylated (1mH3K27, 2mH3K27, and 3mH3K27, respectively) [5]. Hence, either PRC2 must be regulated so as to add one methyl group to certain nucleosomes but two or three to others, or distinct complexes must be responsible for 1m-, 2m-, and 3mH3K27. Consistent with the latter possibility, 2mH3K27 and 3mH3K27, but not 1mH3K27, are absent in Suz12¿/¿ embryos, which lack both Suz12 and Ezh2 protein [6]. Mammalian proteins required for 1mH3K27 have not been identified. Here, we demonstrate that unlike Suz12 and Ezh2, Eed is required not only for 2m- and 3mH3K27 but also global 1mH3K27. These results provide a functionally important distinction between PRC2 complex components and implicate Eed in PRC2-independent histone methylation.
Aurora Kinase Promotes Turnover of Kinetochore Microtubules to Reduce Chromosome Segregation Errors
Creators: name: Salmon, E.D.
name: Hirel, Christophe B.
name: Wan, Xiaohu
name: Cimini, Daniela
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Merotelic kinetochore orientation is a misattachment in which a single kinetochore binds microtubules from both spindle poles rather than just one and can produce anaphase lagging chromosomes, a major source of aneuploidy [1]. Merotelic kinetochore orientation occurs frequently in early mitosis, does not block chromosome alignment at the metaphase plate, and is not detected by the spindle checkpoint 2, 3, 4 and 5. However, microtubules to the incorrect pole are usually significantly reduced or eliminated before anaphase 3 and 6. We discovered that the frequency of lagging chromosomes in anaphase is very sensitive to partial inhibition of Aurora kinase activity by ZM447439 at a dose, 3 μM, that has little effect on histone phosphorylation, metaphase chromosome alignment, and cytokinesis in PtK1 cells. Partial Aurora kinase inhibition increased the frequency of merotelic kinetochores in late metaphase, and the fraction of microtubules to the incorrect pole. Measurements of fluorescence dissipation after photoactivation showed that kinetochore-microtubule turnover in prometaphase is substantially suppressed by partial Aurora kinase inhibition. Our results support a preanaphase correction mechanism for merotelic attachments in which correct plus-end attachments are pulled away from high concentrations of Aurora B at the inner centromere, and incorrect merotelic attachments are destabilized by being pulled toward the inner centromere.
Onthophagus (Onthophagus) krysai Balthasar 1967
Creators: name: Bezděk, Aleš
name: Hájek, Jiří
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Onthophagus
Onthophagus krysai

description: Onthophagus (Onthophagus) krysai Balthasar, 1967
 Onthophagus (s. str.) krysai Balthasar, 1967b: 4.
The holotype is deposited in NMPC (ex coll. V. Balthasar):
HOLOTYPE (J): ‘AFR. occ. Guinea / Kisidougou / Dr. E. Krýsa lgt. [p] // Onthophagus / Krýsai n.sp. / J Balth. [hw] / Holotypus [p, pink label] // Mus. Nat. Pragae / Inv. [p] 65119 [hw, red label] // Holotypus / Onthophagus / kysai [sic!] Balthasar 1967 [hw] // = Pseudosaproecius / portentosus (Felsche) / (Cambefort, 1976) [hw] / DET. / T. Branco [p] 1990 [hw]’.
 Current status. Pseudosaproecius krysai (Balthasar, 1967), see CAMBEFORT (1976).
description: Published as part of Bezděk, Aleš & Hájek, Jiří, 2013, Catalogue of type specimens of beetles (Coleoptera) deposited in the National Museum, Prague, Czech Republic, pp. 387-442 in Acta Entomologica Musei Nationalis Pragae 53 (1) on page 410, DOI: 10.5281/zenodo.5739743
Additional file 3 of Prevalence and associated factors for climatic droplet keratopathy in Kazakhs adults: a cross-sectional study in Tacheng, Xinjiang, China
Creators: name: Hua, Zhixiang
name: Han, Xiaoyan
name: Li, Guoqing
name: Lv, Li
name: He, Xiaolan
name: Gu, Laman
name: Luo, Jianfeng
name: Yang, Jin
Publisher: name: figshare
Year: 2021
Subjects: Cell Biology
Environmental Sciences not elsewhere classified
Biological Sciences not elsewhere classified
Science Policy

description: Additional file 3. Table: Distribution of CDK in different townships.
Divergent Roles for RalA and RalB in Malignant Growth of Human Pancreatic Carcinoma Cells
Creators: name: Kendall, S. DiSean
name: Campbell, Paul M.
name: O'Hayer, Kevin
name: Counter, Christopher M.
name: Lim, Kian-Huat
name: Adam, Stacey J.
name: Der, Channing J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: BACKGROUND: The Ral guanine nucleotide-exchange factors (RalGEFs) serve as key effectors for Ras oncogene transformation of immortalized human cells. RalGEFs are activators of the highly related RalA and RalB small GTPases, although only the former has been found to promote Ras-mediated growth transformation of human cells. In the present study, we determined whether RalA and RalB also had divergent roles in promoting the aberrant growth of pancreatic cancers, which are characterized by the highest occurrence of Ras mutations.

RESULTS: We now show that inhibition of RalA but not RalB expression universally reduced the transformed and tumorigenic growth in a panel of ten genetically diverse human pancreatic cancer cell lines. Despite the apparent unimportant role of RalB in tumorigenic growth, it was nevertheless critical for invasion in seven of nine pancreatic cancer cell lines and for metastasis as assessed by tail-vein injection of three different tumorigenic cell lines tested. Moreover, both RalA and RalB were more commonly activated in pancreatic tumor tissue than other Ras effector pathways.

CONCLUSIONS: RalA function is critical to tumor initiation, whereas RalB function is more important for tumor metastasis in the tested cell lines and thus argues for critical, but distinct, roles of Ral proteins during the dynamic progression of Ras-driven pancreatic cancers.
Local entropic effects of polymers grafted to soft interfaces
Creators: name: Bickel, T.
name: Jeppesen, C.
name: Marques, C. M.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: In this paper, we study the equilibrium properties of polymer chains end-tethered to a fluid membrane. The loss of conformational entropy of the polymer results in an inhomogeneous pressure field that we calculate for gaussian chains. We estimate the effects of excluded volume through a relation between pressure and concentration. Under the polymer pressure, a soft surface will deform. We calculate the deformation profile for a fluid membrane and show that close to the grafting point, this profile assumes a cone-like shape, independently of the boundary conditions. Interactions between different polymers are also mediated by the membrane deformation. This pair-additive potential is attractive for chains grafted on the same side of the membrane and repulsive otherwise.
description: 10 pages, 9 figures
In Vitro FRAP Identifies the Minimal Requirements for Mad2 Kinetochore Dynamics
Creators: name: Mapelli, Marina
name: De Antoni, Anna
name: Transidico, Pietro
name: Faretta, Mario
name: Salmon, Edward D.
name: Ferrari, Karin
name: Ciliberto, Andrea
name: Musacchio, Andrea
name: Simonetta, Marco
name: Massimiliano, Lucia
name: Vink, Martin
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: BACKGROUND: Mad1 and Mad2 are constituents of the spindle-assembly checkpoint, a device coupling the loss of sister-chromatid cohesion at anaphase to the completion of microtubule attachment of the sister chromatids at metaphase. Fluorescence recovery after photobleaching (FRAP) revealed that the interaction of cytosolic Mad2 with kinetochores is highly dynamic, suggesting a mechanism of catalytic activation of Mad2 at kinetochores followed by its release in a complex with Cdc20. The recruitment of cytosolic Mad2 to kinetochores has been attributed to a stable receptor composed of a distinct pool of Mad2 tightly bound to Mad1. Whether specifically this interaction accounts for the kinetochore dynamics of Mad2 is currently unknown.

RESULTS: To gain a precise molecular understanding of the interaction of Mad2 with kinetochores, we reconstituted the putative Mad2 kinetochore receptor and developed a kinetochore recruitment assay with purified components. When analyzed by FRAP in vitro, this system faithfully reproduced the previously described in vivo dynamics of Mad2, providing an unequivocal molecular account of the interaction of Mad2 with kinetochores. Using the same approach, we dissected the mechanism of action of p31(comet), a spindle-assembly checkpoint inhibitor.

CONCLUSIONS: In vitro FRAP is a widely applicable approach to dissecting the molecular bases of the interaction of a macromolecule with an insoluble cellular scaffold. The combination of in vitro fluorescence recovery after photobleaching with additional fluorescence-based assays in vitro can be used to unveil mechanism, stoichiometry, and kinetic parameters of a macromolecular interaction, all of which are important for modeling protein interaction networks.
Evidence for Geomagnetic Imprinting as a Homing Mechanism in Pacific Salmon
Creators: name: Lohmann, Kenneth J.
name: Putman, Nathan F.
name: Noakes, David L.G.
name: Quinn, Thomas P.
name: Klimley, A. Peter
name: Putman, Emily M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: In the final phase of their spawning migration, Pacific salmon use chemical cues to identify their home river, but how they navigate from the open ocean to the correct coastal area has remained enigmatic [1]. To test the hypothesis that salmon imprint on the magnetic field that exists where they first enter the sea and later seek the same field upon return [2-4], we analyzed a 56-year fisheries data set on Fraser River sockeye salmon, which must detour around Vancouver Island to approach the river through either a northern or southern passageway [5, 6]. We found that the proportion of salmon using each route was predicted by geomagnetic field drift: the more the field at a passage entrance diverged from the field at the river mouth, the fewer fish used the passage. We also found that more fish used the northern passage in years with warmer sea surface temperature (presumably because fish were constrained to more northern latitudes). Field drift accounted for 16% of the variation in migratory route used, temperature 22%, and the interaction between these variables 28%. These results provide the first empirical evidence of geomagnetic imprinting in any species and imply that forecasting salmon movements is possible using geomagnetic models.