3,467 research outputs found
Characterization of signalling cross-talk between the EP2 and FP receptors in endometrial epithelial cells
No full textUterine fibroids are benign tumors that arise from the smooth-muscle uterine cells (myometrium) and are the most common uterine disorder occurring in as many as 30% of women over 35 years of age. Despite their frequent occurrence, the etiology of uterine fibroids is not well elucidated. Several studies have shown that numerous tumors can be regulated by cyclooxygenase (COX) enzyme products but their role in uterine fibroids is not well established. The initial aim of the study was to determine the expression level of COX enzymes and prostaglandin receptors in fibroids and autologous myometrium samples from women with fibroids. Real-Time reverse-transcriptase polymerase chain reaction (RT-PCR) revealed that the expression of COX enzymes, EP1, EP2 and EP4 prostanoid receptors and prolactin were not significantly altered while the EP3 subtype receptor was significantly down-regulated in fibroids compared to adjacent myometrium samples. The EP3 receptor has a protective role in tumor development suggesting the role for down-regulation of the receptor in uterine fibroids pathology. In addition, the expression of COX enzymes, prostaglandin receptors and prostaglandin-mediated genes were assessed in endometrium samples from women with and without uterine fibroids in different stages of the menstrual cycle. COX-2 and interleukin-8 (IL-8) mRNA expressions were significantly higher in both proliferative stage and early-mid secretory, EP2 receptor and IL-11 were elevated in the proliferative stage, vascular endothelial growth factor (VEGF) was highly expressed in the early-mid secretory phase while FP receptor was up-regulated in all stages of the menstrual cycle in endometrium samples from women with fibroids. These data suggest that up-regulation of COX-2 and prostaglandin receptors (EP2 and FP) in endometrium can induce expression of angiogenic and mitogenic factors such as VEGF, IL-8 and IL-11 which might act in a paracrine manner on neighboring myometrial/fibroid tissue to promote angiogenesis and facilitate tumor growth. XVII Furthermore, since EP2 and FP receptors were up-regulated in the proliferative phase of endometrium from uterine fibroid patients and the receptors are co-expressed in endometrial adenocarcinoma (Ishikawa) cells, this study investigated a possible cross-talk that influences intracellular signalling by using Ishikawa cells stably expressing the EP2 and FP receptors (FPEP2 cells) as a model cell line. Real-Time RT-PCR, Western blot analysis and immunofluorescence microscopy confirmed stable expression of the EP2 and FP receptors in FPEP2 cells localized to the perinuclear and plasma membrane. Using FPEP2 cells, the integrated effect of Butaprost (EP2 receptor ligand) and PGF (FP receptor ligand) co-administration on inositol phosphate (IP3) and adenosine 3-,5-cyclic monophosphate (cAMP) release was assessed to study a possible heterologous-interaction or cross-talk between the EP2 and FP receptors. The study showed that in FPEP2 cells, PGF alone does not alter cAMP production, but in combination with Butaprost augments EP2 receptor-mediated cAMP release. PGF-mediated potentiation of cAMP release was abolished by antagonism of the FP receptor, inhibition of phospholipase C (PLC) and IP3-receptor whereas inhibition of protein kinase C (PKC) had no effect suggesting the cross-talk is mediated by FP receptor activation of IP3 release. Moreover, inhibition of calcium effectors using calmodulin antagonist (W7) or Ca2+/calmodulin-dependent kinase II (CaMK-II) inhibitor (KN-93) abolished PGF potentiation of Butaprost-mediated cAMP release. Using short interfering RNA (siRNA) molecules targeted against the adenylyl cyclase 3 (AC3) isoform, the study showed the isoform to be responsible for the cross-talk between the FP and EP2 receptors. In order to determine the integrative effects of the EP2 and FP receptors co-activation on gene expression, a whole genome array profiling in FPEP2 cells in response to Butaprost and/or PGF was performed. The gene array revealed 228 genes that are regulated by co-activation of the EP2 and FP receptors that are involved in cell morphology, proliferation and differentiation. XVIII In addition, co-activation of EP2 and FP receptors with their respective ligands enhanced or repressed a set of EP2 receptor-regulated genes. One of the genes identified, SAT1 (Spermidine/ N1-acetyltransferase), was regulated by the EP2 and FP receptors cross-talk via the calcium sensitive AC3 isoform. SAT1, with known role in regulation of tumorigenesis was also up-regulated in the proliferative stage of endometrium samples from women with uterine fibroids suggesting the EP2 and FP receptor cross-talk characterized in vitro can also happen in vivo. In conclusion, this study reports that COX-2, EP2 and FP receptors, VEGF, IL-8, IL-11 and SAT1 are up-regulated in endometrium from women with uterine fibroids. These genes play a major role in development of fibroids by facilitating angiogenesis and cell growth and by inhibiting apoptosis via autocrine/paracrine mechanisms. In addition, this study demonstrates that co-activation of the EP2 and FP receptors results in enhanced release of cAMP via the FP receptor-G +-q-Ca2+-calmodulin pathway by activating the calcium-sensitive AC3 isoform and modulates a molecular switch which alters the trans-activation of a subset single-receptor induced genes that have important functions in the pathogenesis of reproductive pathologies
Remnants and Revenants: politics and violence in the work of Agamben and Derrida
No full textThis is the peer reviewed version of the following article: Frazer, Elizabeth, and Kimberly Hutchings. "Remnants and revenants: politics and violence in the work of Agamben and Derrida." The British Journal of Politics & International Relations 13.2 (2011): 127-144, which has been published in final form at http://dx.doi.org/10.1111/j.1467-856X.2010.00428.x. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Jacques Derrida and Giorgio Agamben both consider the question of whether there can be politics without violence, offering contrasting responses. In the case of Agamben, the remnant (that which remains) is disruptive and destabilising of present institutions; in the case of Derrida the revenant, the spectre, promises a future that is open. This reading of the two theories suggests that Derrida's response to the question of politics and violence is more persuasive than Agamben's. But the abstraction of his argument, like the tensions and contradictions in Agamben's, means that we are not hereby furnished with the resources to think politically about violence
Brisures du romaneque: 'La Malédiction de la Madone', ou d'une pratique ironique du docufiction.
No full textLa Malédiction de la Madone, pubblicato nel 2022, è il primo romanzo in cui Philippe Vilain, scrittore tra i maggiori rappresentanti dell’autofinzione, ab- bandona la narrazione in prima persona per un “docufiction” in terza persona basato sulla vita della camorrista Pupetta Maresca. questo cambio di rotta, an- cor più sorprendente per un autore come Vilain che aveva sempre vilipeso que- sto genere letterario, è occasione di mettere in questione le sue concezioni del romanzo e della letteratura. Ne vien fuori una narrazione tesa tra l’aspirazione a far corpo unico con la sua precedente produzione letteraria e le condizioni im- poste dalla “docufinzionalizzazione” della storia. La Malédiction de la Madone diventa così un vero e proprio laboratorio letterario dove la sperimentazione più fine e pensosa svela inattese punte d’ironia.La Malédiction de la Madone, published in 2022, is the first novel in which Philippe Vilain, a writer among the greatest representatives of autofiction, abandons the first-person narration for a third-person “docufiction” based on the life of the camorrist Pupetta Maresca. This change of course, even more surprising for an author like Vilain who had always vilified this literary genre, is an opportunity to question his conceptions of the novel and of literature. The result is a narrative tended between the aspiration to merge with his previous literary pro- duction and the conditions imposed by “docufictionalization” of the history. The Malédiction de la Madone thus becomes a real literary laboratory where the finest and most thoughtful experimentation reveals unexpected hints of irony
FP-INJECTIVE SEMIRINGS, SEMIGROUP RINGS AND LEAVITT PATH ALGEBRAS
No full textIn this paper we give characterisations of FP-injective semirings (previously termed “exact” semirings in work of the first author). We provide a basic connection between FP-injective semirings and P-injective semirings, and establish that FP-injectivity of semirings is a Morita invariant property. We show that the analogue of the Faith-Menal conjecture (relating FP-injectivity and self-injectivity for rings satisfying certain chain conditions) does not hold for semirings. We prove that the semigroup ring of a locally finite inverse monoid over an FP-injective ring is FP-injective and give a criterion for the Leavitt path algebra of a finite graph to be FP-injective
Alive-FP: Automated Verification of Floating Point Based Peephole Optimizations in LLVM
No full textPeephole optimizations optimize and canonicalize code to enable other optimizations but are error-prone. Our prior research on Alive, a domain-specific language for specifying LLVM’s peephole optimizations, automatically verifies the correctness of integer-based peephole optimizations and generates C++ code for use within LLVM. This paper proposes Alive-FP, an automated verification and code generation framework for floating point based peephole optimizations in LLVM. Alive-FP handles bit precise floating point optimizations and a class of fast-math optimizations involving signed zeros, not-a-number, and infinities. This paper provides multiple encodings for various floating point operations to account for the various kinds of undefined behavior and under-specification in the LLVM’s language reference manual. We have translated all optimizations that belong to this category into Alive-FP. In this process, we have discovered seven wrong optimizations in LLVM.Technical report DCS-TR-72
S-FP-Projective Modules and Dimensions
No full textLet R be a ring and let S be a multiplicative subset of R. An R-module M is said to be a u-S-absolutely pure module if ExtR1N,M is u-S-torsion for any finitely presented R-module N. This paper introduces and studies the notion of S-FP-projective modules, which extends the classical notion of FP-projective modules. An R-module M is called an S-FP-projective module if ExtR1M,N=0 for any u-S-absolutely pure R-module N. We also introduce the S-FP-projective dimension of a module and the global S-FP-projective dimension of a ring. Then, the relationship between the S-FP-projective dimension and other homological dimensions is discussed
Analysis of wavelength detuning, injected power, and injected mode effect on Fabry-Perot laser diode
No full textBasic characteristics of wavelength locked Fabry-Perot laser diode (FP-LD) are analyzed and results are presented by the simulation of a theoretical model of the FP-LD. We use fourth-order Runge-Kutta to solve the rate equation of injection locked FP-LD which has been studied by many researchers. But most of the research are either focused only on wavelength detuning or on the modes of injected beam. Hence we analyze the effect of wavelength detuning, modes of injected beam, injected power on the FP-LD. With these analysis we can conclude the required wavelength detuning, mode for injection, required injected beam power and others depending upon applications. We model FP-LD theoretically and analyze output spectrum without injection locking which contains photon number of each mode and carrier density along with gain spectrum. We added the injected beam term to the rate equation in one or more modes to obtain the spectrum of wavelength locked FP-LD. Injection locked phenomena is observed with sufficient on/off contrast ratio. Various parameters such as wavelength detuning, injected beam power, bias current, and injected modes are changed to analyze output power and spectrum. Analysis on hysteresis width is also done by changing the wavelength detuning, and injected mode number to see the effect on hysteresis width which is important to find proper wavelength detuning, injected power and mode of injected beam required for the different application such as switching, memory and others. The analysis will help to find effective parameters to meet the demand of power effective optical devices for future optical networking system
Long-term orbital period behaviour of low mass ratio contact binaries GR Vir and FP Boo
No full text32nd International Physics Congress of Turkish-Physical-Society (TPS) -- SEP 06-09, 2016 -- Bodrum, TURKEYIn this study, we investigated orbital period variations of two low mass ratio contact binaries GR Vir and FP Boo based on published minima times. From the O-C analysis, it was found that FP Boo indicates orbital period decrease while the period of GR Vir is increasing. Mass transfer process was used to explain increase and decrease in the orbital periods. In the O-C diagrams of both systems periodic variations also exist. Cyclic changes can be explained as being the result of a light-travel time effect via a third component around the eclipsing binaries. In order to interpret of cyclic orbital period changes for GR Vir, which has late-type components, possible magnetic activity cycles of the components have been also considered.Turkish Phys So
[[alternative]]An Efficient Approach for Maintaining Association Rules based on Adjusting FP-tree Structure
No full text[[abstract]]In this thesis, the issue of mining and maintaining association rules in a large database of customer transactions is studied. The maintenance of association rules can be mapped into the problem of maintaining frequent itemsets in the database. Because the mining of association rules is time-consuming, we need an efficient approach to maintain the frequent itemsets when the database is updated. In this study, a general incremental updating technique is proposed for maintaining the frequent itemsets discovered in a database in the cases including insertion, deletion, and modification of transactions in the database. An efficient algorithm, called AFPIM (Adjusting FP-tree for Incremental Mining), is designed based on adjusting FP-tree structures. Our approach uses a FP-tree structure to store the compact information of transactions involving frequent and pre-frequent items in the original database. In most cases, the new FP-tree structure of the updated database can be obtained by adjusting FP-tree of the original database according to the changed transactions without needing to rescan the original database. Experimental results show that AFPIM outperforms the existing algorithms in terms of the execution time.
Convolutional neural network based attenuation correction for <sup>123</sup>I-FP-CIT SPECT with focused striatum imaging
No full textSPECT imaging with 123I-FP-CIT is used for diagnosis of neurodegenerative disorders like Parkinson's disease. Attenuation correction (AC) can be useful for quantitative analysis of 123I-FP-CIT SPECT. Ideally, AC would be performed based on attenuation maps (μ-maps) derived from perfectly registered CT scans. Such μ-maps, however, are most times not available and possible errors in image registration can induce quantitative inaccuracies in AC corrected SPECT images. Earlier, we showed that a convolutional neural network (CNN) based approach allows to estimate SPECT-aligned μ-maps for full brain perfusion imaging using only emission data. Here we investigate the feasibility of similar CNN methods for axially focused 123I-FP-CIT scans. We tested our approach on a high-resolution multi-pinhole prototype clinical SPECT system in a Monte Carlo simulation study. Three CNNs that estimate μ-maps in a voxel-wise, patch-wise and image-wise manner were investigated. As the added value of AC on clinical 123I-FP-CIT scans is still debatable, the impact of AC was also reported to check in which cases CNN based AC could be beneficial. AC using the ground truth μ-maps (GT-AC) and CNN estimated μ-maps (CNN-AC) were compared with the case when no AC was done (No-AC). Results show that the effect of using GT-AC versus CNN-AC or No-AC on striatal shape and symmetry is minimal. Specific binding ratios (SBRs) from localized regions show a deviation from GT-AC ≤ 2.5% for all three CNN-ACs while No-AC systematically underestimates SBRs by 13.1%. A strong correlation (r ≥ 0.99) was obtained between GT-AC based SBRs and SBRs from CNN-ACs and No-AC. Absolute quantification (in kBq ml-1) shows a deviation from GT-AC within 2.2% for all three CNN-ACs and of 71.7% for No-AC. To conclude, all three CNNs show comparable performance in accurate μ-map estimation and 123I-FP-CIT quantification. CNN-estimated μ-map can be a promising substitute for CT-based μ-map.RST/Biomedical Imagin
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