Matching Items (50)
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Description

We address the near-collinear expansion of multiparticle NMHV amplitudes, namely, the heptagon and octagons in the dual language of null polygonal super Wilson loops. In particular, we verify multiparticle factorization of charged pentagon transitions in terms of pentagons for single flux-tube excitations within the framework of refined operator product expansion.

We address the near-collinear expansion of multiparticle NMHV amplitudes, namely, the heptagon and octagons in the dual language of null polygonal super Wilson loops. In particular, we verify multiparticle factorization of charged pentagon transitions in terms of pentagons for single flux-tube excitations within the framework of refined operator product expansion. We find a perfect agreement with available tree and one-loop data.

ContributorsBelitsky, Andrei (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-06-03
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Description

Scattering amplitudes in maximally supersymmetric gauge theory receive a dual description in terms of the expectation value of the super Wilson loop stretched on a null polygonal contour. This makes the analysis amenable to nonperturbative techniques. Presently, we elaborate on a refined form of the operator product expansion in terms

Scattering amplitudes in maximally supersymmetric gauge theory receive a dual description in terms of the expectation value of the super Wilson loop stretched on a null polygonal contour. This makes the analysis amenable to nonperturbative techniques. Presently, we elaborate on a refined form of the operator product expansion in terms of pentagon transitions to compute twist-two contributions to NMHV amplitudes. To start with, we provide a novel derivation of scattering matrices starting from Baxter equations for flux-tube excitations propagating on magnon background. We propose bootstrap equations obeyed by pentagon form factors with nonsinglet quantum numbers with respect to the R-symmetry group and provide solutions to them to all orders in 't Hooft coupling. These are then successfully confronted against available perturbative calculations for NMHV amplitudes to four-loop order.

ContributorsBelitsky, Andrei (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-05-05
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Description

We address the near-collinear expansion of NMHV six-particle scattering amplitudes at strong value of the 't Hooft coupling in planar maximally supersymmetric Yang–Mills theory. We complement recent studies of this observable within the context of the Pentagon Operator Product Expansion, via the dual superWilson loop description, by studying effects of

We address the near-collinear expansion of NMHV six-particle scattering amplitudes at strong value of the 't Hooft coupling in planar maximally supersymmetric Yang–Mills theory. We complement recent studies of this observable within the context of the Pentagon Operator Product Expansion, via the dual superWilson loop description, by studying effects of multiple scalar exchanges that accompany (or not) massive flux-tube excitations. Due to the fact that holes have a very small, nonperturbatively generated mass mh which is exponentially suppressed in the 't Hooft coupling, their exchanges must be resummed in the ultraviolet limit, T <<1/mh. This procedure yields a contribution to the expectation value of the superloop which enters on equal footing with the classical area — a phenomenon which was earlier observed for MHV amplitudes. In all components, the near-massless scalar exchanges factorize from the ones of massive particles, at leading order in strong coupling.

ContributorsBelitsky, Andrei (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-08-20
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Description

The Operator Product Expansion for null polygonal Wilson loop in planar maximally supersymmetric Yang–Mills theory runs systematically in terms of multi-particle pentagon transitions which encode the physics of excitations propagating on the color flux tube ending on the sides of the four-dimensional contour. Their dynamics was unraveled in the past

The Operator Product Expansion for null polygonal Wilson loop in planar maximally supersymmetric Yang–Mills theory runs systematically in terms of multi-particle pentagon transitions which encode the physics of excitations propagating on the color flux tube ending on the sides of the four-dimensional contour. Their dynamics was unraveled in the past several years and culminated in a complete description of pentagons as an exact function of the 't Hooft coupling. In this paper we provide a solution for the last building block in this program, the SU(4) matrix structure arising from internal symmetry indices of scalars and fermions. This is achieved by a recursive solution of the Mirror and Watson equations obeyed by the so-called singlet pentagons and fixing the form of the twisted component in their tensor decomposition. The non-singlet, or charged, pentagons are deduced from these by a limiting procedure.

ContributorsBelitsky, Andrei (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-08-31
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Description

Insect immune systems can recognize specific pathogens and prime offspring immunity. High specificity of immune priming can be achieved when insect females transfer immune elicitors into developing oocytes. The molecular mechanism behind this transfer has been a mystery. Here, we establish that the egg-yolk protein vitellogenin is the carrier of

Insect immune systems can recognize specific pathogens and prime offspring immunity. High specificity of immune priming can be achieved when insect females transfer immune elicitors into developing oocytes. The molecular mechanism behind this transfer has been a mystery. Here, we establish that the egg-yolk protein vitellogenin is the carrier of immune elicitors. Using the honey bee, Apis mellifera, model system, we demonstrate with microscopy and western blotting that vitellogenin binds to bacteria, both Paenibacillus larvae – the gram-positive bacterium causing American foulbrood disease – and to Escherichia coli that represents gram-negative bacteria. Next, we verify that vitellogenin binds to pathogen-associated molecular patterns; lipopolysaccharide, peptidoglycan and zymosan, using surface plasmon resonance. We document that vitellogenin is required for transport of cell-wall pieces of E. coli into eggs by imaging tissue sections. These experiments identify vitellogenin, which is distributed widely in oviparous species, as the carrier of immune-priming signals. This work reveals a molecular explanation for trans-generational immunity in insects and a previously undescribed role for vitellogenin.

ContributorsSalmela, Heli (Author) / Amdam, Gro (Author) / Freitak, Dalial (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-07-31
Description

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats.

Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits.

Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation.

ContributorsSadd, Ben M. (Author) / Barribeau, Seth M. (Author) / Bloch, Guy (Author) / de Graaf, Dirk C. (Author) / Dearden, Peter (Author) / Elsik, Christine G. (Author) / Gadau, Juergen (Author) / Grimmelikhuijzen, Cornelis J. P. (Author) / Hasselmann, Martin (Author) / Lozier, Jeffrey D. (Author) / Robertson, Hugh M. (Author) / Smagghe, Guy (Author) / Stolle, Eckart (Author) / Van Vaerenbergh, Matthias (Author) / Waterhouse, Robert M. (Author) / Bornberg-Bauer, Erich (Author) / Klasberg, Steffen (Author) / Bennett, Anna K. (Author) / Camara, Francisco (Author) / Guigo, Roderic (Author) / Hoff, Katharina (Author) / Mariotti, Marco (Author) / Munoz-Torres, Monica (Author) / Murphy, Terence (Author) / Santesmasses, Didac (Author) / Amdam, Gro (Author) / Beckers, Matthew (Author) / Beye, Martin (Author) / Biewer, Matthias (Author) / Bitondi, Marcia MG (Author) / Blaxter, Mark L. (Author) / Bourke, Andrew FG (Author) / Brown, Mark JF (Author) / Buechel, Severine D. (Author) / Cameron, Rossanah (Author) / Cappelle, Kaat (Author) / Carolan, James C. (Author) / Christiaens, Olivier (Author) / Ciborowski, Kate L. (Author) / Clarke, David F. (Author) / Colgan, Thomas J. (Author) / Collins, David H. (Author) / Cridge, Andrew G. (Author) / Dalmay, Tamas (Author) / Dreier, Stephanie (Author) / du Plessis, Louis (Author) / Duncan, Elizabeth (Author) / Erler, Silvio (Author) / Evans, Jay (Author) / Falcon, Talgo (Author) / Flores, Kevin (Author) / Freitas, Flavia CP (Author) / Fuchikawa, Taro (Author) / Gempe, Tanja (Author) / Hartfelder, Klaus (Author) / Hauser, Frank (Author) / Helbing, Sophie (Author) / Humann, Fernanda (Author) / Irvine, Frano (Author) / Jermiin, Lars S (Author) / Johnson, Claire E. (Author) / Johnson, Reed M (Author) / Jones, Andrew K. (Author) / Kadowaki, Tatsuhiko (Author) / Kidner, Jonathan H. (Author) / Koch, Vasco (Author) / Kohler, Arian (Author) / Kraus, F. Bernhard (Author) / Lattorff, H. Michael G. (Author) / Leask, Megan (Author) / Lockett, Gabrielle A. (Author) / Mallon, Eamonn B. (Author) / Marco Antonio, David S. (Author) / Marxer, Monika (Author) / Meeus, Ivan (Author) / Moritz, Robin FA (Author) / Nair, Ajay (Author) / Napflin, Kathrin (Author) / Nissen, Inga (Author) / Niu, Jinzhi (Author) / Nunes, Francis MF (Author) / Oakeshott, John G. (Author) / Osborne, Amy (Author) / Otte, Marianne (Author) / Pinheiro, Daniel G. (Author) / Rossie, Nina (Author) / Rueppell, Olav (Author) / Santos, Carolina G (Author) / Schmid-Hempel, Regula (Author) / Schmitt, Bjorn D. (Author) / Schulte, Christina (Author) / Simoes, Zila LP (Author) / Soares, Michelle PM (Author) / Swevers, Luc (Author) / Winnebeck, Eva C. (Author) / Wolschin, Florian (Author) / Yu, Na (Author) / Zdobnov, Evgeny M (Author) / Aqrawi, Peshtewani K (Author) / Blakenburg, Kerstin P (Author) / Coyle, Marcus (Author) / Francisco, Liezl (Author) / Hernandez, Alvaro G. (Author) / Holder, Michael (Author) / Hudson, Matthew E. (Author) / Jackson, LaRonda (Author) / Jayaseelan, Joy (Author) / Joshi, Vandita (Author) / Kovar, Christie (Author) / Lee, Sandra L. (Author) / Mata, Robert (Author) / Mathew, Tittu (Author) / Newsham, Irene F. (Author) / Ngo, Robin (Author) / Okwuonu, Geoffrey (Author) / Pham, Christopher (Author) / Pu, Ling-Ling (Author) / Saada, Nehad (Author) / Santibanez, Jireh (Author) / Simmons, DeNard (Author) / Thornton, Rebecca (Author) / Venkat, Aarti (Author) / Walden, Kimberly KO (Author) / Wu, Yuan-Qing (Author) / Debyser, Griet (Author) / Devreese, Bart (Author) / Asher, Claire (Author) / Blommaert, Julie (Author) / Chipman, Ariel D. (Author) / Chittka, Lars (Author) / Fouks, Bertrand (Author) / Liu, Jisheng (Author) / O'Neill, Meaghan P (Author) / Sumner, Seirian (Author) / Puiu, Daniela (Author) / Qu, Jiaxin (Author) / Salzberg, Steven L (Author) / Scherer, Steven E (Author) / Muzny, Donna M. (Author) / Richards, Stephen (Author) / Robinson, Gene E (Author) / Gibbs, Richard A. (Author) / Schmid-Hempel, Paul (Author) / Worley, Kim C (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-04-24
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Description
The muon problem of flavor physics presents a rich opportunity to study beyond standard model physics. The as yet undiscovered bound state (μ+μ-), called true muonium, presents a unique opportunity to investigate the muon problem. The near-future experimental searches for true muonium will produce it relativistically, preventing the easy application

The muon problem of flavor physics presents a rich opportunity to study beyond standard model physics. The as yet undiscovered bound state (μ+μ-), called true muonium, presents a unique opportunity to investigate the muon problem. The near-future experimental searches for true muonium will produce it relativistically, preventing the easy application of non-relativistic quantum mechanics. In this thesis, quantum field theory methods based on light-front quantization are used to solve an effective Hamiltonian for true muonium in the Fock space of |μ+μ-> , |μ+μ-γ> , |e+e->, |e+e-γ>, |τ+τ-> , and |τ+τ-γ> . To facilitate these calculations a new parallel code, True Muonium Solver With Front-Form Techniques (TMSWIFT), has been developed. Using this code, numerical results for the wave functions, energy levels, and decay constants of true muonium have been obtained for a range of coupling constants α. Work is also presented for deriving the effective interaction arising from the |γγ sector’s inclusion into the model.
ContributorsLamm, Henry (Author) / Lebed, Richard F (Thesis advisor) / Belitsky, Andrei (Committee member) / Alarcon, Ricardo (Committee member) / Easson, Damien (Committee member) / Arizona State University (Publisher)
Created2016
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Description

In this paper we study the four-point correlation function of the energy–momentum supermultiplet in theories with N = 4 superconformal symmetry in four dimensions. We present a compact form of all component correlators as an invariant of a particular abelian subalgebra of the N = 4 superconformal algebra. This invariant

In this paper we study the four-point correlation function of the energy–momentum supermultiplet in theories with N = 4 superconformal symmetry in four dimensions. We present a compact form of all component correlators as an invariant of a particular abelian subalgebra of the N = 4 superconformal algebra. This invariant is unique up to a single function of the conformal cross-ratios which is fixed by comparison with the correlation function of the lowest half-BPS scalar operators. Our analysis is independent of the dynamics of a specific theory, in particular it is valid in N = 4 super Yang–Mills theory for any value of the coupling constant. We discuss in great detail a subclass of component correlators, which is a crucial ingredient for the recent study of charge-flow correlations in conformal field theories. We compute the latter explicitly and elucidate the origin of the interesting relations among different types of flow correlations previously observed in arXiv:1309.1424.

ContributorsBelitsky, Andrei (Author) / Hohenegger, S. (Author) / Korchemsky, G. P. (Author) / Sokatchev, E. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-01-07
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Description

In vitro rearing is an important and useful tool for honey bee (Apis mellifera L.) studies. However, it often results in intercastes between queens and workers, which are normally are not seen in hive-reared bees, except when larvae older than three days are grafted for queen rearing. Morphological classification (queen

In vitro rearing is an important and useful tool for honey bee (Apis mellifera L.) studies. However, it often results in intercastes between queens and workers, which are normally are not seen in hive-reared bees, except when larvae older than three days are grafted for queen rearing. Morphological classification (queen versus worker or intercastes) of bees produced by this method can be subjective and generally depends on size differences. Here, we propose an alternative method for caste classification of female honey bees reared in vitro, based on weight at emergence, ovariole number, spermatheca size and size and shape, and features of the head, mandible and basitarsus. Morphological measurements were made with both traditional morphometric and geometric morphometrics techniques. The classifications were performed by principal component analysis, using naturally developed queens and workers as controls. First, the analysis included all the characters. Subsequently, a new analysis was made without the information about ovariole number and spermatheca size. Geometric morphometrics was less dependent on ovariole number and spermatheca information for caste and intercaste identification. This is useful, since acquiring information concerning these reproductive structures requires time-consuming dissection and they are not accessible when abdomens have been removed for molecular assays or in dried specimens. Additionally, geometric morphometrics divided intercastes into more discrete phenotype subsets. We conclude that morphometric geometrics are superior to traditional morphometrics techniques for identification and classification of honey bee castes and intermediates.

ContributorsDe Souza, Daiana A. (Author) / Wang, Ying (Author) / Kaftanoglu, Osman (Author) / De Jong, David (Author) / Amdam, Gro (Author) / Goncalves, Lionel S. (Author) / Francoy, Tiago M. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-04-20
Description
Major Depressive Disorder (MDD) is a common mental disorder that can affect individuals at nearly every stage of life. Women are especially vulnerable to MDD in part, from ovarian hormone level fluctuations. In this thesis, I focused on MDD using a rat model in middle-age to explore potential sex differences

Major Depressive Disorder (MDD) is a common mental disorder that can affect individuals at nearly every stage of life. Women are especially vulnerable to MDD in part, from ovarian hormone level fluctuations. In this thesis, I focused on MDD using a rat model in middle-age to explore potential sex differences in response to a corticosterone (CORT) – induced depressive-like state. Estradiol (E2), a naturally occurring steroid sex hormone in humans and rats, is implicated in mood changes, which is especially prominent during the menopause transition. CORT, a stress hormone, was used to create a depressive-like state in middle-aged female (F) and male (M) rats with their gonads surgically removed. This produced the following independent treatment groups: Sex (F, M), CORT (vehicle = V ml/kg, C 40mg/kg), E2 (V 0.1 ml, E 0.3µg/0.1ml). CORT and E2 injections were injected daily, s.c) for 7 days before behavioral testing began and continued throughout the study when behavior was assessed. For my honor’s thesis, I focused on the social interaction test and elevated plus maze to investigate whether CORT enhanced social avoidance and anxiety, and whether E2 mitigated the CORT effects. In the social interaction test, three new behaviors were assessed (interacting, grooming, and immobility) to better understand exploratory and anxiety profiles of the rats, and these behaviors were quantified over two 5-minute periods in the 10-minute trial. These new quantifications showed that for the female rats, C+E and V+V enhanced the interaction with the novel rat significantly more than an inanimate object, which was not observed in the females given CORT only or E2 only. The males in all conditions showed a significant preference for side with the novel rat compared to the object, however no treatment differences were observed. In both sexes, the overall time spent interacting decreased in the second five minutes of quantification compared to the first five minutes. No effects were observed with grooming or immobility, in part from the high variability across rats. For EPM, female rats treated with CORT and E2 exhibited a lower anxiety index than compared to female rats given CORT only, indicating that E2 mitigated the depressive-like effects of CORT. Males showed no CORT or E2 effects. The result in part supported my hypothesis, as the CORT-treated females exhibited reduced socialization and E2 improved socialization in CORT-treated females, as this was seen in the F-C-E group. Interestingly, CORT failed to produce a depressive-like effect in males in both behavioral tests, which was an unexpected outcome. These results suggest that administration of E2 with CORT mitigated the depressive-like state created by CORT in female rats, however failed to produce these outcomes in males. The outcome of this work will give us insight into the potential mechanisms that may contribute to sex differences with MDD.
ContributorsSladkova, Sara (Author) / Conrad, Cheryl (Thesis director) / Amdam, Gro (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor)
Created2024-05