scholarly journals Exact effective interactions and 1/4-BPS dyons in heterotic CHL orbifolds

2019 ◽  
Vol 7 (3) ◽  
Author(s):  
Guillaume Bossard ◽  
Charles Cosnier-Horeau ◽  
Boris Pioline
Keyword(s):  
Black Holes ◽  
Effective Interaction ◽  
Three Dimensional ◽  
Theta Series ◽  
Siegel Modular Form ◽  
Tree Level ◽  
Type I ◽  
Type Ii ◽  
Effective Interactions ◽  
Perturbative Corrections

Motivated by precision counting of BPS black holes, we analyze six-derivative couplings in the low energy effective action of three-dimensional string vacua with 16 supercharges. Based on perturbative computations up to two-loop, supersymmetry and duality arguments, we conjecture that the exact coefficient of the \nabla^2(\nabla\phi)^4∇2(∇ϕ)4 effective interaction is given by a genus-two modular integral of a Siegel theta series for the non-perturbative Narain lattice times a specific meromorphic Siegel modular form. The latter is familiar from the Dijkgraaf-Verlinde-Verlinde (DVV) conjecture on exact degeneracies of 1/4-BPS dyons. We show that this Ansatz reproduces the known perturbative corrections at weak heterotic coupling, including tree-level, one- and two-loop corrections, plus non-perturbative effects of order e^{-1/g_3^2}e−1/g32. We also examine the weak coupling expansions in type I and type II string duals and find agreement with known perturbative results, . In the limit where a circle in the internal torus decompactifies, our Ansatz predicts the exact \nabla^2 F^4∇2F4 effective interaction in four-dimensional CHL string vacua, along with infinite series of exponentially suppressed corrections of order e^{-R}e−R from Euclideanized BPS black holes winding around the circle, and further suppressed corrections of order e^{-R^2}e−R2 from Taub-NUT instantons. We show that instanton corrections from 1/4-BPS black holes are precisely weighted by the BPS index predicted from the DVV formula, including the detailed moduli dependence. We also extract two-instanton corrections from pairs of 1/2-BPS black holes, demonstrating consistency with supersymmetry and wall-crossing, and estimate the size of instanton-anti-instanton contributions.

scholarly journals Two-loop superstring five-point amplitudes. Part II. Low energy expansion and S-duality

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Eric D’Hoker ◽  
Carlos R. Mafra ◽  
Boris Pioline ◽  
Oliver Schlotterer
Keyword(s):  
Moduli Space ◽  
Effective Interaction ◽  
Type Ii ◽  
Leading Order ◽  
Effective Interactions ◽  
Heterotic String Theory ◽  
Genus Two ◽  
Genus One ◽  
Graph Function ◽  
Point Amplitude

Abstract In an earlier paper, we constructed the genus-two amplitudes for five external massless states in Type II and Heterotic string theory, and showed that the α′ expansion of the Type II amplitude reproduces the corresponding supergravity amplitude to leading order. In this paper, we analyze the effective interactions induced by Type IIB superstrings beyond supergravity, both for U(1)R-preserving amplitudes such as for five gravitons, and for U(1)R-violating amplitudes such as for one dilaton and four gravitons. At each order in α′, the coefficients of the effective interactions are given by integrals over moduli space of genus-two modular graph functions, generalizing those already encountered for four external massless states. To leading and sub-leading orders, the coefficients of the effective interactions D2ℛ5 and D4ℛ5 are found to match those of D4ℛ4 and D6ℛ4, respectively, as required by non-linear supersymmetry. To the next order, a D6ℛ5 effective interaction arises, which is independent of the supersymmetric completion of D8ℛ4, and already arose at genus one. A novel identity on genus-two modular graph functions, which we prove, ensures that up to order D6ℛ5, the five-point amplitudes require only a single new modular graph function in addition to those needed for the four-point amplitude. We check that the supergravity limit of U(1)R-violating amplitudes is free of UV divergences to this order, consistently with the known structure of divergences in Type IIB supergravity. Our results give strong consistency tests on the full five-point amplitude, and pave the way for understanding S-duality beyond the BPS-protected sector.

scholarly journals Altered affinity of insulin-like growth factor II (IGF-II) for receptors and IGF-binding proteins, resulting from limited modifications of the IGF-II molecule

1991 ◽  
Vol 278 (1) ◽  
pp. 249-254 ◽  
Author(s):  
Y Oh ◽  
M W Beukers ◽  
H M Pham ◽  
P A Smanik ◽  
M C Smith ◽  
...  
Keyword(s):  
Amino Acids ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Type I ◽  
Type Ii ◽  
Factor Ii ◽  
N Terminus ◽  
Severe Impairment ◽  
Igf Binding ◽  
Terminal Amino

The binding affinities of seven analogues of recombinant human insulin-like growth factor II (hIGF-II) were characterized for the IGF type-I and type-II receptors and insulin receptors, as well as for IGF-binding protein (IGFBP)-1, IGFBP-2, IGFPB-3 and human serum IGFBPs. A switch of two of the three cysteine bridges in hIGF-II, 9-47 and 46-51 to 9-46 and 47-51, severely impaired the binding of this analogue to all receptors and to the IGFBPs. The affinities for the IGF type-I receptor and the IGFBPs were decreased over 100-fold, while the binding to the insulin receptor and the IGF type-II receptor was less affected, with a 6-10-fold decrease in affinity. Slight modifications of the N-terminus had only minor effects upon the binding of hIGF-II to the IGFBPs or to the receptors. Deletion of both the N-terminal amino acid and the two C-terminal amino acids resulted in moderate decreases in affinity, with a 60% decrease in affinity for IGFBP-1 and the IGF type-I receptor. Acetylation of the N-terminus of Ala1 and the epsilon-nitrogen of Lys65 decreased the affinity, by 60-90%, of hIGF-II for all of the IGFBPs and receptors. The experiments involving acetylation of IGF-II or switching of its cysteine bridges indicated that these modifications (no substitution, deletion or addition of any of the 67 amino acids of hIGF-II) may lead to a severe impairment of the binding affinity of IGF-II for both the IGFBPs and the receptors. Acetylation of the epsilon-nitrogen of Lys65, which causes a charge change, or alteration of the three-dimensional structure, as shown by the cysteine bridge switch, lead to a severe impairment of the binding affinity for the binding proteins and for the receptors. In general, care should be taken with the synthesis of analogues and the interpretation of resulting binding data, since affinity alterations ascribed to amino acid changes may instead be caused by alterations of the charge or the three-dimensional structure of the protein.

scholarly journals Study On The Application of Preoperative Three-Dimensional CT Angiography of Perigastric Arteries In Laparoscopic Radical Gastrectomy

2022 ◽  
Author(s):  
Peng Liu ◽  
Wenbin Yu ◽  
Meng Wei ◽  
Danping Sun ◽  
Xin Zhong ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Blood Loss ◽  
Three Dimensional ◽  
Classification Model ◽  
Type I ◽  
Radical Gastrectomy ◽  
Type Ii ◽  
Type Iii ◽  
Type Iv ◽  
Type V

Abstract Objection: To investigate the clinical value and significance of preoperative three-dimensional computerized tomography angiography (CTA) in laparoscopic radical gastrectomy for gastric cancer.Methods: The clinical data were analyzed retrospectively from 214 gastric cancer patients. We grouped according to whether to perform CTA. The gastric peripheral artery was classified according to CTA images of patients in the CTA group, and we compared and analyzed the difference of the data between the two groups.Results: The celiac trunk was classified according to Adachi classification: Type I (118/125, 94.4%),Type II (3/125, 2.4%),Type III (0/125, 0%),Type IV (1/125, 0.8%),Type V (2/125, 1.6%),Type VI (1/125, 0.8%).Hepatic artery classification was performed according to Hiatt classification standard:Type I (102/125, 81.6％),Type II (9/125, 7.2%),Type III (6/125, 4.8%),Type IV (2/125, 1.6%),Type V (3/125, 2.4%),Type VI (0, 0%),Others (3/125, 2.4%).And this study combined vascular anatomy and clinical surgical risk to establish a new splenic artery classification model. It was found that the operation time and estimated blood loss in the CTA group were significantly lower than those in the non-CTA group. In addition, the blood loss in the CTA group combined with ICG (Indocyanine Green) labeled fluorescence laparoscopy was significantly less than that in the group without ICG labeled. Conclusion: Preoperative CTA can objectively evaluate the vascular course and variation of patients, and then avoid the risk of operation, especially in combination with ICG labeled fluorescence laparoscopy, can further improve the quality of operation.

scholarly journals The severity of developmental dysplasia of the hip does not correlate with the abnormality in pelvic incidence

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Rongshan Cheng ◽  
Muyin Huang ◽  
Willem Alexander Kernkamp ◽  
Huiwu Li ◽  
Zhenan Zhu ◽  
...  
Keyword(s):  
Pelvic Incidence ◽  
Sagittal Plane ◽  
Three Dimensional ◽  
Developmental Dysplasia ◽  
Control Group ◽  
Type I ◽  
Type Ii ◽  
Computed Tomography Images ◽  
Significant Difference ◽  
Dysplasia Of The Hip

Abstract Background The purpose of this study was to investigate the association between the severity of Developmental dysplasia of the hip (DDH) and the abnormality in pelvic incidence (PI). Methods This was a retrospective study analyzing 53 DDH patients and 53 non-DDH age-matched controls. Computed tomography images were used to construct three-dimensional pelvic model. The Crowe classification was used to classify the severity of DDH. The midpoint of the femoral head centers and sacral endplates were projected to the sagittal plane of the pelvis. The PI was defined as the angle between a line perpendicular to the sacral plate at its midpoint and a line connecting this point to the axis of the femoral heads. Independent sample t-tests were used to compare the differences between the PI of DDH group and the non-DDH controls group. Kendall’s coefficient of concordance was used to determine the correlation between the severity of DDH and PI. Results Patients with DDH had a significantly (p = 0.041) higher PI than the non-DDH controls (DDH 47.6 ± 8.2°, normal 44.2 ± 8.8°). Crowe type I patients had a significantly (p = 0.038) higher PI (48.2 ± 7.6°) than the non-DDH controls. No significant difference between the PI in Crowe type II or III patients and the PI in non-DDH controls were found (Crowe type II, 50.2 ± 9.6°, p = 0.073; Crowe type III, 43.8 ± 7.2°, p = 0.930). No correlation was found between the severity of DDH and the PI (r = 0.091, p = 0.222). Conclusions No correlation was found between the severity of DDH and the PI. The study confirmed that the PI in DDH (Crowe type I) group was higher than that of the non-DDH control group, while the PI does not correlate with the severity of DDH.

scholarly journals Preliminary Deformational Studies on a Finite Element Model of the Nasal Septum Reveals Key Areas for Septal Realignment and Reconstruction

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Kyrin Liong ◽  
Shu Jin Lee ◽  
Heow Pueh Lee
Keyword(s):  
Nasal Septum ◽  
Preoperative Planning ◽  
Three Dimensional ◽  
Element Model ◽  
Septal Cartilage ◽  
Type I ◽  
Type Ii ◽  
Anterior Nasal Spine ◽  
Force Direction ◽  
Three Dimensional Models

Background. With the current lack of clinically relevant classification methods of septal deviation, computer-generated models are important, as septal cartilage is indistinguishable on current imaging methods, making preoperative planning difficult. Methods. Three-dimensional models of the septum were created from a CT scan, and incremental forces were applied. Results. Regardless of the force direction, with increasing force, the septum first tilts (type I) and then crumples into a C shape (type II) and finally into an S shape (type III). In type I, it is important to address the dislocation in the vomer-ethmoid cartilage junction and vomerine groove, where stress is concentrated. In types II and III, there is intrinsic fracture and shortening of the nasal septum, which may be dislocated off the anterior nasal spine. Surgery aims to relieve the posterior buckling and dislocation, with realignment of the septum to the ANS and possible spreader grafts to buttress the fracture sites. Conclusion. By identifying clinically observable septal deviations and the areas of stress concentration and dislocation, a straighter, more stable septum may be achieved.

scholarly journals Identification of actin-, alpha-actinin-, and vinculin-containing plaques at the lateral membrane of epithelial cells.

1986 ◽  
Vol 102 (5) ◽  
pp. 1843-1852 ◽  
Author(s):  
D Drenckhahn ◽  
H Franz
Keyword(s):  
Plasma Membrane ◽  
Cross Sections ◽  
Three Dimensional ◽  
Intercellular Junctions ◽  
Classical Type ◽  
Type I ◽  
Type Ii ◽  
Microscopic Studies ◽  
Prostatic Epithelium ◽  
Human Intestinal Epithelium

In this paper, a new type of spot desmosome-like junction (type II plaque) is described that is scattered along the entire lateral plasma membrane of rat and human intestinal epithelium. Ultrastructurally type II plaques differed from the classical type of epithelial spot desmosome ("macula adherens", further denoted as type I desmosome) by weak electron density of the membrane-associated plaque material, association of the plaques with microfilaments rather than intermediate filaments, and poorly visible material across the intercellular space. Thus, type II plaques resemble cross-sections of the zonula adherens. Immunofluorescence-microscopic studies were done using antibodies to a main protein associated with the plaques of type I desmosomes (desmoplakin I) and to the three major proteins located at the plaques of the zonula adherens (actin, alpha-actinin, and vinculin). Two types of plaques were visualized along the lateral surface of intestinal and prostatic epithelium: (a) the type I desmosomes, which were labeled with anti-desmoplakin but did not bind antibodies to actin, alpha-actinin, and vinculin, and (b) a further set of similarly sized plaques, which bound antibodies to actin, alpha-actinin, and vinculin but were not stained with anti-desmoplakin. Three-dimensional computer reconstruction of serial sections double-labeled with anti-desmoplakin and anti-alpha-actinin further confirmed that both types of plaques are spatially completely separated from each other along the lateral plasma membrane. The computer graphs further revealed that the actin-, alpha-actinin-, and vinculin-containing plaques have the tendency to form clusters, a feature also typical of type II plaques. It is suggested that the type II plaques represent spot desmosome-like intercellular junctions, which, like the zonula adherens, appear to be linked to the actin filament system. As the type II plaques cover a considerable part of the lateral cell surface, they might play a particular role in controlling cellular shape and intercellular adhesion.

Percutaneous sinus angiography and three-dimensional CT imaging showing morphological and draining features of venous malformations in soft tissue

2014 ◽  
Vol 30 (6) ◽  
pp. 418-428 ◽  
Author(s):  
Si-Ming Yuan ◽  
Chang-Sheng Zhou ◽  
Lei Cui ◽  
Yao Guo ◽  
Jun Wang ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Contrast Media ◽  
Three Dimensional ◽  
Surgical Removal ◽  
Type I ◽  
Type Ii ◽  
Three Dimensional Imaging ◽  
Type Iii ◽  
Choice Of Treatment ◽  
Main Vein

Objective Venous malformation (VM) is a common vascular malformation in soft tissue. Its morphological and draining features, relationship with main vein, and hemodynamics in the lesion are not completely clear till now. Above information is important for choice of treatment. Methods From January 2012 to December 2013, 23 patients were enrolled into this study. Percutaneous puncture into the lesion was made and contrast media was injected into venous sinus. Immediately after that CT scan was performed, and repeated several minutes later. Then three-dimensional imaging was performed to show the morphology and draining veins of VMs, and the relevant main veins. The hemodynamics in the lesion was also evaluated. Results All patients underwent successful examination. Three-dimensional imaging showed an irregular shape of VM. Based on the draining features, VMs were classified into three types: (1) Type I (7/23): malformation without visible draining vein; (2) Type II (10/23): malformation with normal draining vein; (3) Type III (6/23): malformation with abnormal dilated draining vein. The flow in type I VMs was slow. Contrast media retained in the lesion for more than 1 day. The flow in type III VMs was fast. Contrast media flowed away rapidly. The flow of type II VMs was between type I and type III. According to above information and adjacent anatomy, all patients received suitable treatment, including sclerotherapy with absolute ethanol and bleomycin A5, intralesional copper wires retention, surgical removal, and combinational therapy of the above methods. Conclusions This procedure can clearly show the morphological and draining features of VM and its relationship with main vein, and further evaluate the hemodynamics in the lesion, which are helpful for the choice of treatment.

scholarly journals Ideal type-II Weyl points in topological circuits

2020 ◽  
Author(s):  
Rujiang Li ◽  
Bo Lv ◽  
Huibin Tao ◽  
Jinhui Shi ◽  
Yidong Chong ◽  
...  
Keyword(s):  
Spectral Characteristics ◽  
Three Dimensional ◽  
Surface States ◽  
Ideal Type ◽  
Type I ◽  
Type Ii ◽  
Ideal System ◽  
Lc Resonator ◽  
Topological Surface ◽  
Group Velocities

Abstract Weyl points (WPs), nodal degenerate points in three-dimensional (3D) momentum space, are said to be ‘ideal’ if they are symmetry-related and well-separated, and reside at the same energy and far from nontopological bands. Although type-II WPs have unique spectral characteristics compared with type-I counterparts, ideal type-II WPs have not yet been reported due to the lack of an experimental platform with enough flexibility to produce strongly tilted dispersion bands. Here we experimentally realize a topological circuit that hosts only topological bands with a minimal number of four ideal type-II WPs. By stacking two-dimensional (2D) layers of inductor-capacitor (LC) resonator dimers with the broken parity inversion symmetry (P), we achieve a strongly tilted band structure with two group velocities in the same direction, and topological surface states in an incomplete bandgap. Our results establish an ideal system for the further study of Weyl physics and other exotic topological phenomena.

Cartilage-Specific Matrix and Integrin Expression in Three-Dimensional Articular Chondrocyte Cultures Overexpressing Human Interleukin-10

2008 ◽  
Vol 1 ◽  
pp. CMAMD.S560
Author(s):  
Riccarda D. Müller ◽  
Thilo John ◽  
Benjamin Kohl ◽  
Anja Feldner ◽  
Hala Zreiqat ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Collagen Type ◽  
Articular Chondrocytes ◽  
Three Dimensional ◽  
3D Culture ◽  
Type I ◽  
Β1 Integrin ◽  
Type Ii ◽  
Collagen Type Ii ◽  
Chondrocyte Cultures

Interleukin (IL)-10 overexpression inhibits joint inflammation, however the effect of high local concentrations of IL-10 on chondrocyte homeostasis remains unclear. The aim of this study was to determine the effects of IL-10 overexpression on cartilage matrix production in three-dimensional (3D) chondrocyte cultures. Human articular chondrocytes were transduced with adenoviral vectors alone (adv/empty) or by vectors either overexpressing enhanced green fluorescence protein (adv/EGFP) or human IL-10 (adv/hIL-10) before their transfer to a 3D culture system. Non-transduced chondrocytes were used as controls. The expression of IL-10 or EGFP was confirmed using ELISA or flow cytometry. Chondrocytes synthesis of collagen types II and I, aggrecan, fibronectin and β1-integrin was determined over a period of 14 days post transduction using flow cytometry or immunohistochemistry. adv/EGFP or adv/IL-10 transduced chondrocytes expressed EGFP or secreted IL-10 detectable over the 2 weeks culture period. No suppression of collagen type II, aggrecan or β1-integrin synthesis by IL-10 overexpression was found and the deposition of collagen type I and fibronectin remained unaffected compared to the controls. IL-10 overexpression does not impair key features of chondrocytes differentiated phenotype (e.g. collagen type II and aggrecan expression) suggesting the potential use of IL-10 for gene therapeutic approaches in the joint.

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