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We consider various integrable two-parameter deformations of the AdS3 × S3 × T4 superstring with quantum group symmetry. Working on the string worldsheet in light-cone gauge and to quadratic order in fermions, we obtain their common massive tree-level two-body S matrix, which matches the expansion of the conjectured exact q-deformed S matrix. We then analyze the behavior of the exact S matrix under mirror transformation — a double Wick rotation on the worldsheet — and find that it satisfies a mirror duality relation analogous to the distinguished q-deformed AdS5 × S5 S matrix in the one parameter deformation limit. Finally, we show that the fermionic q-deformed AdS5 × S5 S matrix also satisfies such a relation., Journal of High Energy Physics, 2021 (9), ISSN:1126-6708, ISSN:1029-8479

The relationship between $T\bar{T}$ deformations and the uniform light-cone gauge, first noted in arXiv:1804.01998, provides a powerful generating technique for deformed models. We recall this construction, distinguishing between changes of the gauge frame, which do not affect the theory, and genuine deformations. We investigate the geometric interpretation of the latter and argue that they affect the global features of the geometry before gauge fixing. Exploiting a formal relation between uniform light-cone gauge and static gauge in a T-dual frame, we interpret such a change as a TsT transformation involving the two light-cone coordinates. In the static-gauge picture, the $T\bar{T}$ CDD factor then has a natural interpretation as a Drinfel'd-Reshetikhin twist of the worldsheet S matrix. To illustrate these ideas, we find the geometries yielding a $T\bar{T}$ deformation of the worldsheet S matrix of pp-wave and Lin-Lunin-Maldacena backgrounds.

PURPOSE AND BACKGROUND: This study retrospectively compares diagnostic performance of 1.5 T versus 3 T non-echo planar diffusion weighted imaging with or without additional T1 and T2 sequences in the detection of residual and/or recurrent cholesteatoma.METHODS: Patients with clinically suspected recurrent cholesteatoma or postoperative routine survey MR who subsequently underwent surgical procedure were retrospectively included (135 patients, 164 operated ears) from a large database. Patients underwent 1.5 T (128 ears) or 3 T MRI (36 ears), with non-echo planar DWI, T1 and T2 acquisitions. Two radiologists independently reassessed the images. Definitive surgical diagnosis was used as gold standard. Sensitivity, specificity and diagnostic odds ratio were evaluated.RESULTS: According to surgical diagnosis a cholesteatoma was present in 124 of 164 ears, corresponding with a prevalence of 75%. Sensitivity and specificity were lower for 3 T compared to 1.5 T, irrespective of whether additional T1 and T2-weighted sequences were used or not. Diagnostic odds ratios were higher for 1.5 T (34 and 12 for reader 1 and 2, respectively) compared to 3 T (3 and 4 for reader 1 and 2, respectively). Adding T1 and T2 sequences lowers sensitivity but increases specificity.CONCLUSION: Non-epi DWI for the detection of residual/recurrent cholesteatoma is preferably performed on 1.5 T scanners over 3 T. The use of additional sequences regarding detection of cholesteatoma is debatable as it lowers sensitivity but increases specificity. However, these sequences may also be of use in diagnosing complications and planning surgical procedures in some hospitals.

We discuss homogeneous Yang-Baxter deformations of integrable sigma models in terms of twist operators. We show that the twist operators behave as the classical analogue of a Drinfeld twist, for all abelian and almost abelian deformations. We also use twist operators to rederive the well-known interpretation of TsT transformations -- equivalent to abelian deformations -- in terms of twisted boundary conditions. We discuss complications in extending this boundary condition picture to non-abelian deformations., v3, 15 pages, corrected typo in equation (2.4), otherwise matches v2 and published version

Purpose of Review To give an up-to-date overview of the strengths and weaknesses of current imaging modalities in diagnosis and follow-up of skull base osteomyelitis (SBO). Recent Findings CT and MRI are both used for anatomical imaging, and nuclear techniques aid in functional process imaging. Hybrid techniques PET-CT and PET-MRI are the newest modalities which combine imaging strengths. Summary No single modality is able to address the scope of SBO. A combination of functional and anatomical imaging is needed, in the case of newly suspected SBO we suggest the use of PET-MRI (T1, T2, T1-FS-GADO, DWI) and separate HRCT for diagnosis and follow-up.

The spectral problem for the ${\rm AdS}_5\times {\rm S}^5$ superstring and its dual planar maximally supersymmetric Yang-Mills theory can be efficiently solved through a set of functional equations known as the quantum spectral curve. We discuss how the same concepts apply to the $\eta$-deformed ${\rm AdS}_5\times {\rm S}^5$ superstring, an integrable deformation of the ${\rm AdS}_5\times {\rm S}^5$ superstring with quantum group symmetry. This model can be viewed as a trigonometric version of the ${\rm AdS}_5\times {\rm S}^5$ superstring, like the relation between the XXZ and XXX spin chains, or the sausage and the ${\rm S}^2$ sigma models for instance. We derive the quantum spectral curve for the $\eta$-deformed string by reformulating the corresponding ground-state thermodynamic Bethe ansatz equations as an analytic $Y$ system, and map this to an analytic $T$ system which upon suitable gauge fixing leads to a $\mathbf{P} \mu$ system -- the quantum spectral curve. We then discuss constraints on the asymptotics of this system to single out particular excited states. At the spectral level the $\eta$-deformed string and its quantum spectral curve interpolate between the ${\rm AdS}_5\times {\rm S}^5$ superstring and a superstring on "mirror" ${\rm AdS}_5\times {\rm S}^5$, reflecting a more general relationship between the spectral and thermodynamic data of the $\eta$-deformed string. In particular, the spectral problem of the mirror ${\rm AdS}_5\times {\rm S}^5$ string, and the thermodynamics of the undeformed ${\rm AdS}_5\times {\rm S}^5$ string, are described by a second rational limit of our trigonometric quantum spectral curve, distinct from the regular undeformed limit., Comment: 32+37 pages; 6 figures. v2: added references

Short-term results from seventy-six patients receiving a bone-anchored hearing implant installed with a novel minimally invasive surgery technique

A large class of the recently found unimodular nonabelian homogeneous Yang-Baxter deformations of the AdS_5 x S^5 superstring can be realized as sequences of noncommuting TsT transformations. I show that many of them are duals to various noncommutative versions of supersymmetric Yang-Mills theory, structurally determined directly in terms of the associated r matrices, in line with previous expectations in the literature., v4, 9 pages letter format, no figures, minor typos corrected, otherwise matches published version

We discuss a quantum deformation of the Green-Schwarz superstring on flat space, arising as a contraction limit of the corresponding deformation of AdS_5 x S^5. This contraction limit turns out to be equivalent to a previously studied limit that yields the so-called mirror model - the model obtained from the light cone gauge fixed AdS_5 x S^5 string by a double Wick rotation. Reversing this logic, the AdS_5 x S^5 superstring is the double Wick rotation of a quantum deformation of the flat space superstring. This quantum deformed flat space string realizes symmetries of timelike kappa-Poincare type, and is T dual to dS_5 x H^5, indicating interesting relations between symmetry algebras under T duality. Our results directly extend to AdS_2 x S^2 x T^6 and AdS_3 x S^3 x T^4, and beyond string theory to many (semi)symmetric space coset sigma models, such as for example a deformation of the four dimensional Minkowski sigma model with timelike kappa-Poincare symmetry. We also discuss possible null and spacelike deformations., v3, published version, 12 pages

We consider various homogeneous Yang-Baxter deformations of the AdS_5 x S^5 superstring that can be obtained from the eta-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the eta-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which implies that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which do correspond to supergravity solutions., Comment: v3, 25 pages, typos corrected, further minor typographical changes, published version

We introduce a series of articles reviewing various aspects of integrable models relevant to the AdS/CFT correspondence. Topics covered in these reviews are: classical integrability, Yangian symmetry, factorized scattering, the Bethe ansatz, the thermodynamic Bethe ansatz, and integrable structures in (conformal) quantum field theory. In the present article we highlight how these concepts have found application in AdS/CFT, and provide a brief overview of the material contained in this series., v2, published version

We discuss the spectral problem for integrable superstrings on generically twisted AdS 5 × S 5 , meaning all its orbifolds and TsT transformed versions. We explicitly give the asymptotic description of these theories through a twisted transfer matrix, and carefully match the geometric deformations with twists allowed by integrability. We then discuss the mirror TBA equations that describe these theories at finite size. This unifies the treatment of various specific deformations previously considered in this setting, and extends it to completely general twists.

Interesting deformations of AdS5 × S5 such as the gravity dual of noncommutative SYM and Schodinger spacetimes have recently been shown to be integrable. We clarify questions regarding the reality and integrability properties of the associated construction based on R matrices that solve the classical Yang-Baxter equation, and present an overview of manifestly real R matrices associated to the various deformations. We also discuss when these R matrices should correspond to TsT transformations, which not all do, and briefly analyze the symmetries preserved by these deformations, for example finding Schrodinger superalgebras that were previously obtained as subalgebras of $$ \mathfrak{p}\mathfrak{s}\mathfrak{u} $$ (2, 2|4). Our results contain a (singular) generalization of an apparently non-TsT deformation of AdS5 × S5, whose status as a string background is an interesting open question.

Via an appropriate field redefinition of the fermions, we find a set of conditions under which light cone gauge fixed world sheet theories of strings on two different backgrounds are related by a double Wick rotation. These conditions take the form of a set of transformation laws for the background fields, complementing a set of transformation laws for the metric and B field we found previously with a set for the dilaton and RR fields, and are compatible with the supergravity equations of motion. Our results prove that at least to second order in fermions, the AdS_5 x S^5 mirror model which plays an important role in the field of integrability in AdS/CFT, represents a string on `mirror AdS_5 x S^5', the background that follows from our transformations. We discuss analogous solutions for AdS_3 x S^3 x T^4 and AdS_2 x S^2 x T^6. The main ingredient in our derivation is the light cone gauge fixed action for a string on an (almost) completely generic background, which we explicitly derive to second order in fermions., v2, updated discussion on target space interpretation, elaborated discussion on minor points, content matches published version, 28 pages, 3 figures

Background: Innate immune recognition via Toll-like receptors (TLRs) on barrier cells like epithelial cells has been shown to influence the regulation of local immune responses. Here we determine expression level variations and functionality of TLRs in nasal epithelial cells from healthy donors. Methods: Expression levels of the different TLRs on primary nasal epithelial cells from healthy donors derived from inferior turbinates was determined by RT-PCR. Functionality of the TLRs was determined by stimulation with the respective ligand and evaluation of released mediators by Luminex ELISA. Results: Primary nasal epithelial cells express different levels of TLR1-6 and TLR9. We were unable to detect mRNA of TLR7, TLR8 and TLR10. Stimulation with Poly(I: C) resulted in a significant increased secretion of IL-4, IL-6, RANTES, IP-10, MIP-1 beta, VEGF, FGF, IL-1RA, IL-2R and G-CSF. Stimulation with PGN only resulted in significant increased production of IL-6, VEGF and IL-1RA. Although the expression of TLR4 and co-stimulatory molecules could be confirmed, primary nasal epithelial cells appeared to be unresponsive to stimulation with LPS. Furthermore, we observed huge individual differences in TLR agonist-induced mediator release, which did not correlate with the respective expression of TLRs. Conclusion: Our data suggest that nasal epithelium seems to have developed a delicate system of discrimination and recognition of microbial patterns. Hypo-responsiveness to LPS could provide a mechanism to dampen the inflammatory response in the nasal mucosa in order to avoid a chronic inflammatory response. Individual, differential expression of TLRs on epithelial cells and functionality in terms of released mediators might be a crucial factor in explaining why some people develop allergies to common inhaled antigens, and others do not

Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally.

Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally.

We discuss the spectrum of a string propagating on eta-deformed AdS_5 x S^5 by treating its world-sheet theory as an integrable quantum field theory. The exact S-matrix of this field theory is given by a q-deformation of the AdS_5 x S^5 world-sheet S-matrix with real deformation parameter. By considering mirror (double Wick-rotated) versions of these world-sheet theories we give the Thermodynamic Bethe Ansatz description of their exact finite size spectra. Interestingly, this class of models maps onto itself under the mirror transformation. At the level of the string this appears to say that the light-cone worldsheet theories of strings on particular pairs of backgrounds are related by a double Wick rotation, a feature we call 'mirror duality'. We provide a partial check of these statements at the level of the sigma model by considering reduced actions and their corresponding (mirror) giant magnon solutions., v2, reference added, arxiv author name corrected, 36 pages, 2 figures

We discuss the description of generic excited states in the quantum deformed AdS5 × S5 mirror thermodynamic Bethe ansatz and derive the associated Y-system. This Y-system shows an interesting new feature; it depends explicitly on the excited state under consideration. Similarly, it also depends on twisted boundary conditions. We construct the asymptotic solution of these TBA and Y-system equations by deriving the twisted transfer matrix for the quantum deformed Hubbard model and finding the deformed mirror bound state dressing phase. This asymptotic construction is insensitive to the precise nature of the deformation, and thereby provides a nontrivial check of the interesting new features which arise precisely at roots of unity., Journal of High Energy Physics, 2013 (2), ISSN:1126-6708, ISSN:1029-8479

We give a pedagogical introduction to the thermodynamic Bethe ansatz, a method that allows us to describe the thermodynamics of integrable models whose spectrum is found via the (asymptotic) Bethe ansatz. We set the stage by deriving the Fermi-Dirac distribution and associated free energy of free electrons, and then in a similar though technically more complicated fashion treat the thermodynamics of integrable models, focusing on the one dimensional Bose gas with delta function interaction as a clean pedagogical example, secondly the XXX spin chain as an elementary (lattice) model with prototypical complicating features in the form of bound states, and finally the SU(2) chiral Gross-Neveu model as a field theory example. Throughout this discussion we emphasize the central role of particle and hole densities, whose relations determine the model under consideration. We then discuss tricks that allow us to use the same methods to describe the exact spectra of integrable field theories on a circle, in particular the chiral Gross-Neveu model. We moreover discuss the simplification of TBA equations to Y systems, including the transition back to integral equations given sufficient analyticity data, in simple examples., introductory review article, v3, 46 pages, 9 figures, minor typographical changes to match published version

Starting with a discussion of the general applicability of the simplified mirror TBA equations to simple deformations of the AdS_5 x S^5 superstring, we proceed to study a specific type of orbifold to which the undeformed simplified TBA equations directly apply. We then use this set of equations, as well as Luscher's approach, to determine the NLO wrapping correction to the energy of what we call the orbifolded Konishi state, and show that they perfectly agree. In addition we discuss wrapping corrections to the ground state energy of the orbifolded model under consideration., Comment: 26 pages, 5 figures, v2: corrected typos, added a short discussion on the ground state of the model; as submitted to J. Phys. A

We discuss fermionic reductions of type IIA superstrings on AdS{sub 4}xCP{sup 3} in relation to the conjectured AdS{sub 4}/CFT{sub 3} duality. The superstring theory is described by means of a coset model construction, which is classically integrable. We discuss the global light-cone symmetries of the action and related {kappa}-symmetry gauge choices, and also present the complete quartic action in covariant form with respect to these. Further, we study integrable (fermionic) reductions, in particular, a reduction yielding a quadratic action of two complex fermions on the string world-sheet. Interestingly, this model appears to be exactly the same as the corresponding integrable reduction found in the AdS{sub 5}xS{sup 5} case.

Synchronous bilateral malignancy in the parotid glands is extremely rare. The English literature reveals nine case reports. The most common synchronous bilateral malignancies are acinic cell carcinoma. Epithelial–myoepithelial carcinoma is an uncommon neoplasm comprising 1% of all salivary gland tumours. In this case report, we describe, to our best of knowledge, the first case of a patient with a synchronous bilateral epithelial–myoepithelial carcinoma of the parotid gland. The clinical histopathological and immunohistochemical peculiarities are elucidated. Imaging studies like ultrasonography are mandatory for both parotid glands and upper necks in the clinical presence of a unilateral parotid gland tumour.

Objectives. The reliability and discriminative capacity of hand function tests were studied in order to obtain tests suitable for the evaluation of local treatment of an arthritic metacarpophalangeal (MCP) joint. Methods. To assess reliability, hand function tests were measured twice without local treatment of the MCP in 25 patients with rheumatoid arthritis (RA). The discriminative capacity of the hand function tests with respect to the results of intra-articular corticosteroid injection was assessed in 28 RA patients with synovitis of an MCP joint. Thereafter, a randomized, observer-blind treatment study was performed in 21 RA patients with synovitis of an MCP joint; 10 of the patients were treated. Results/Conclusions. This study showed that the efficacy of treatment of an MCP joint can be measured by several reliable and discriminative parameters: passive flexion, the Ritchie pain score, swelling, the Arthritis Impact Measurements Scales question about buttoning clothes, and visual analogue scale questions about the activity of the disease and swelling of the joint. K : Rheumatoid arthritis, MCP joint, Hand function, Corticosteroids, Impairment, Disability.

Equations using variance components in exposure data to predict attenuation and standard error of exposure--response slopes have been published recently. However, to date, no comparisons have been made between results of applying these equations to a real data set with the exposure-response relations estimated directly.Data on lung function parameters and personal inhalable and respirable dust exposure levels from the European carbon black respiratory health study were used. The predicted attenuation and standard error of the relation between current inhalable and respirable dust levels and lung function parameters (FVC and FEV(1)) were calculated for various exposure grouping schemes. These results were compared with the observed exposure-response relations. Workers were grouped by Job Category, the combination of factory and Job Category and five a posteriori created Exposure Groups. In addition, the individual approach was also used, as exposure data were available for each worker.The rank orders of the coefficients from the regression analyses using the different grouping schemes were similar to those predicted by the equations, although the differences were larger than predicted. When using inhalable dust exposure, the predicted standard errors of the exposure-response slopes were slightly lower than those estimated directly; for respirable dust the predicted standard errors were about a factor two to three smaller than those from the regression analyses. When considering FVC, the predicted exposure-response relations were all statistically significant, whilst the observed relation was only significant when using the five a posteriori Exposure Groups. When reviewing the relations between dust exposure and level of FEV(1), all relations were statistically significant, with the exception of the (observed) relation between respirable dust and FEV(1), when the individual approach was used.Using different grouping schemes for estimating exposure can have large effects on the slope and standard error of the exposure-response relation. It is, therefore, important that the effect of the different grouping schemes on the level and precision of the exposure-response slope be estimated. Despite violation of most of the assumptions when applying the equations to predict attenuation and the standard error of the exposure-response slope, the similarities in predicted and observed exposure-response relations and standard errors are indicative of the robustness of these equations. Therefore, the equations appear to be a useful tool in establishing the most efficient way of utilizing exposure measurements.

Changes of the stomach, duodenum and small bowel due to gastrin-producing tumors are important signs for the diagnosis of Zollinger-Ellison syndrome. Peptic esophagitis and calcification of a gastrin producing tumor of the pancreas are typical changes in the Zollinger-Ellison syndrome.