cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The receptor tyrosine kinase RET is a Hsp90 client protein and is degraded upon exposure to 17-AAG.
Creators: name: Alfano, Luigi
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2009

description: Molecular alterations of the receptor tyrosin kinase RET are involved in the pathogenesis of thyroid cancer. Germline point mutations in the extracellular and intracellular domains of the receptor are responsible of a group of inherited cancer diseases defined as Multiple Endocrine Neplasia type 2 syndromes (MEN2), whose major feature is represented by Medullary Thyroid Carcinoma (MTC). Somatic point mutations of RET are also found in around 40% of sporadic MTC. Hsp90 is part of the molecular chaperone machinery involved in mediating correct folding and stabilization of client proteins. Hsp90 chaperone fuctions in concert with the action of a multitude of other chaperone and co-chaperone proteins like Hsp70, Aha1 and CDC37; its activity depends on ATP and can be hindred by Geldanamycin-like compounds. Several kinases implicated in the process of neoplastic transformation are clients of Hsp90. In this thesis, we demonstrated that RET is a Hsp90 client protein. In RAT1 murine fibroblasts, stably transfected with RET wt or RET C634R oncogenic mutant, the Geldanamycin-derived drug 17- AAG was able to induce a proteasome dependent degradation of the receptor. Treatment with 17-AAG caused dissociation of Hsp90-RET complex and stabilized the interaction between RET and Hsp70 leading to recruitment of the Hsp70 interacting E3-ligase CHIP. Polyubiquitination by E3-ligases is commonly a destruction signal that mediates recognition of the targetted proteins by proteasome. Overexpression of CHIP wt, but not of two different CHIP defective mutants, CHIP-TPR and CHIP-ΔU, induced RET polyubiquitination and degradation. Interestingly, 17-AAG obstructed RET oncogenic signalling, decreasing RET C634R mediated activation of Ras-MAPK pathway and blocking transactivation of AP1-responsive and Mycgene promoters. We could not observe any changes in sensitivity to 17-AAG-induced degradation among several RET MTC-associated mutants carrying mutations in the intracellular domain of the receptor, the region where Hsp90 chaperone has been shown to bind to receptor tyrosine kinases. In human MTC cells carrying oncogenic RET mutants, Hsp90 inhibition by 17-AAG induced receptor degradation and signalling hindrance as shown by reduced phosphorylation of Shc and MAPK proteins. In such cells, 17-AAG caused a robust growth arrest, measured by decreased incorporation of BrdU, but failed to induce apoptosis. In conclusion we demonstrated that RET is a Hsp90 client protein and the chaperone is required for folding and stabilization of the receptor.
The crosstalk between Dendritic and Natural Killer cells together with the function of Tumor Associated Macrophages (TAM) represent novel cancer-related targets for Human Immunodeficiency Type-1 Protease Inhibitors
Creators: name: Ciaglia, Elena
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2009

description: Inflammatory conditions and infections in selected organs increase the risk of cancer. In the tumor microenvironment, smoldering inflammation contributes to proliferation and survival of malignant cells, angiogenesis, metastasis and subversion of adaptive immunity. The human immunodeficiency virus (HIV) infection is characterized by increased risk of several solid tumors due to its inherent nature of weakening the immune system. Recent observations point to a lower incidence of some cancers in patients treated with protease inhibitor (PI) cocktail such as HAART (Highly Active Anti-Retroviral Therapy). Human Immunodeficiency Type-1 Virus protease inhibitors (HIV-1-PIs) originally designed to block selectively the aspartic protease of HIV-1, also shown the ability to modulate a variety of biological functions, including the immune response, by mechanisms largely independent from their anti-viral activity. Herein, we investigate the effects of PIs on differentiation programs of monocytes toward: (a) dendritic cells (DC); (b) Tumor Associated Macrophages-like cells (TAM-like). Differentiation of human circulating monocytes in the presence of PIs led to generation of DC with atypical phenotype, including low level of Cd1a, and DC-SIGN, a receptor that enables DC to bind HIV-1 virions in tissues, and carry them to lymphonodes. Moreover, DC generated in the presence of ritonavir also fail to terminally differentiate, and secrete lower amounts of IL- 12 and IL-15, in response to bacterial endotoxin (LPS). This phenomenon parallels their inability to prime NK cells, and become resistant to NK-mediated cytotoxicity. The exposure of monocytes to certains PIs determines generation of Tumour Associated Macrophages-Like cells with an atypical phenotype, including higher level of the co-stimulatory molecules CD86, and lower expression of ILT3, a receptor playing an imunosuppressive role. Accordingly, in response to LPS, TAM-like cells generated in the presence of PIs, secrete lower amount of MM9 and VEGF, a phenomenon accompanying their ability to release more GM-CSF. Altogether, these findings demonstrate the ability of PIs to modulate the differentiation programs of human monocytes. The remakable property of certain PIs to modulate phenotypes and functionalities of DC and TAM, might open novel perspectives for immune-intervention aimed to manipulate the cancer inflammatory milieu.
Prognosis and adjuvant treatment effects in very young women (below 35 years) with operable breast cancer
Creators: name: Cancello, Giuseppe
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2009

description: Background: There is limited knowledge about prognosis of selected breast cancer subtypes among very young women Patients and Methods: We explored patterns of recurrence by age according to four immunohistochemically-defined tumor subtypes: triple negative, HER2 positive (and) endocrine receptor absent, Luminal A and Luminal B (ER-positive and/or PR-positive and either HER2-positive and/or high Ki67) in 2970 premenopausal patients with pT1-3, pN0-3 and M0 breast cancer. Results: Patients below 35 years of age (315, 11%) presented a significantly increased risk of recurrence and death (HR=1.65, 95%CI 1.30-2.10 and HR=1.78, 95%CI 1.12-2.85, respectively) when compared with older patients (2655, 89%) with similar characteristics of disease. This was true considering patients with luminal B (HR 1.62, 95%CI, 1.21-2.18, for DFS; HR 2.09, 95%CI, 0.96-4.53, for OS) and with triple-negative (HR 2.04, 95%CI, 1.11-3.72, for DFS; HR 2.20, 95%CI, 1.10-4.41, for OS) breast cancer, observing the highest risk of recurrence in the younger patients with HER2 positive breast cancer (HR 2.37, 95% CI, 1.12-5.02), when compared with older patients. Conclusions: Very young patients with triple negative, luminal B, or HER2 positive breast cancer have a worse prognosis when compared with older patients with similar characteristics of disease.
Public Life and Space of Petaling Street: Reading the Mutable Street from Socio-Spatial Perspectives
Creators: name: Veronica Ng, Jean Kian
Publisher: name: TuEngr Group
Year: 2021
Subjects: Petaling Street
Pedestrianised street
Social space
Public space
Asian street
Place identity
Street liveability.

description: International Transaction Journal of Engineering, Management, & Applied Sciences & Technologies, 12, 2, 12A2H: 1-14
Atomium: The astounding complexity of the near circumstellar environment of the M-type AGB star R Hydrae. I. Morpho-kinematical interpretation of CO and SiO emission
Creators: name: Homan, Ward
name: Pimpanuwat, Bannawit
name: Herpin, Fabrice
name: Danilovich, Taissa
name: McDonald, Iain
name: Wallström, Sofia H. J.
name: Richards, Anita M. S.
name: Baudry, Alain
name: Sahai, Raghvendra
name: Millar, Tom J.
name: de Koter, Alex
name: Gottlieb, C. A.
name: Kervella, Pierre
name: Montargès, Miguel
name: Van de Sande, Marie
name: Decin, Leen
name: Zijlstra, Albert
name: Etoka, Sandra
name: Jeste, Manali
name: Müller, Holger S. P.
name: Maes, Silke
name: Malfait, Jolien
name: Menten, Karl
name: Plane, John
name: Lee, Kelvin
name: Waters, Rens
name: Wong, Ka Tat
name: Lagadec, Eric
name: Gobrecht, David
name: Yates, Jeremy
name: Price, Daniel
name: Cannon, Emily
name: Bolte, Jan
name: De Ceuster, Frederik
name: Nuth, Joe
name: Sindel, Jan philip
name: Kee, Dylan
name: Gray, Malcolm D.
name: Mellah, Ileyk El
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Evolved low- to intermediate-mass stars are known to shed their gaseous envelope into a large, dusty, molecule-rich circumstellar nebula which typically develops a high degree of structural complexity. Most of the large-scale, spatially correlated structures in the nebula are thought to originate from the interaction of the stellar wind with a companion. As part of the Atomium large programme, we observed the M-type asymptotic giant branch (AGB) star R Hydrae with ALMA. The morphology of the inner wind of R Hya, which has a known companion at ~3500 au, was determined from maps of CO and SiO obtained at high angular resolution. A map of the CO emission reveals a multi-layered structure consisting of a large elliptical feature at an angular scale of ~10'' that is oriented along the north-south axis. The wind morphology within the elliptical feature is dominated by two hollow bubbles. The bubbles are on opposite sides of the AGB star and lie along an axis with a position angle of ~115 deg. Both bubbles are offset from the central star, and their appearance in the SiO channel maps indicates that they might be shock waves travelling through the AGB wind. An estimate of the dynamical age of the bubbles yields an age of the order of 100 yr, which is in agreement with the previously proposed elapsed time since the star last underwent a thermal pulse. When the CO and SiO emission is examined on subarcsecond angular scales, there is evidence for an inclined, differentially rotating equatorial density enhancement, strongly suggesting the presence of a second nearby companion. The position angle of the major axis of this disc is ~70 deg in the plane of the sky. We tentatively estimate that a lower limit on the mass of the nearby companion is ~0.65 Msol on the basis of the highest measured speeds in the disc and the location of its inner rim at ~6 au from the AGB star.
description: 21 pages, 23 figures
Origine locale degli rna presinaptici e ruolo della sintesi proteica sinaptica nella plasticità cerebrale
Creators: name: Cefaliello, Carolina
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2006

description: Il lavoro di ricerca descritto nella tesi riguarda la caratterizzazione e il ruolo del sistema di espressione genica delle terminazioni nervose del neurone. A questo scopo si sono utilizzati preparati modello del calamaro e del ratto nei quali è già ben nota la presenza di sistemi locali di sintesi proteica.
Nel calamaro, la localizzazione nel lobo ottico delle terminazioni nervose dei fotocettori retinici ha consentito di dimostrare che RNA presinaptico è sintetizzato localmente, presumibilmente nelle vicine cellule gliali. In considerazione del fatto che nelle stesse terminazioni è presente un attivo sistema di sintesi proteica, i dati dimostrano che le regioni presinaptiche sono in grado di utilizzare un sistema locale di espressione genica, basato sulla stretta collaborazione con le cellule gliali perisinaptiche.
D’altra parte, nel ratto, i dati ottenuti con frazioni sinaptosomali preparate da diverse macroregioni del cervello hanno permesso di identificare due proteine sinaptiche, rispettivamente da 66.5 kDa e 87.6 kDa, la cui sintesi locale è notevolmente aumentata in seguito ad addestramento degli animali per un compito di evitamento attivo a due vie, ma non per un compito molto più semplice di abitudine spaziale. Di conseguenza, i dati dimostrano che le regioni sinaptiche del mammifero sono direttamente coinvolte nei processi di plasticità cerebrale a lungo termine indotti dall’apprendimento.
La transizione dal lavoro alla pensione: meccanismi istituzionali di regolazione e strategie d’azione individuali in due siti industriali Alfa Romeo
Creators: name: Pirone, Francesco
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2006

description: La ricerca si focalizza sui meccanismi di regolazione della transizione dal lavoro alla pensione. Lo studio analizza i meccanismi di mercato, istituzionali e culturali che producono l’uscita precoce dei lavoratori anziani dal mercato del lavoro, in considerazione della tendenza demografica all’invecchiamento sociale e delle trasformazioni strutturali del mercato del lavoro nel senso di una sempre maggiore flessibilizzazione e individualizzazione dei rapporti di lavoro. Vengono poi analizzati i principali mutamenti nei sistemi previdenziali e i meccanismi che nelle fasi di crescita economica hanno contribuito all’uscita precoce dal mercato del lavoro verso il pensionamento dei lavoratori anziani e che poi, negli anni Novanta, a seguito della crisi finanziaria del welfare, hanno portato all’irrigidimento dei meccanismi di accesso alla pensione e alla riduzione drastica dei percorsi istituzionali di uscita dal mercato del lavoro. La ricerca è stata ulteriormente sviluppata attraverso uno studio di caso focalizzato sulle strategie individuali di transizione dal lavoro alla pensione dei lavoratori con più di 50 anni, provenienti da due siti industriali Alfa Romeo (Gruppo Fiat): quello di Arese in provincia di Milano e quello di Pomigliano d’Arco in provincia di Napoli. L’indagine di campo è stata basata su interviste qualitative a lavoratori anziani con le quali sono state raccolte biografie lavorative ed è stata approfondita la dimensione soggettiva del passaggio dal lavoro alla pensione. Dall’indagine emerge, da una parte, un quadro articolato dei meccanismi di spinta e di attrazione che condizionano le scelte individuali tra lavoro e non-lavoro nella parte conclusiva del ciclo lavorativo, dall’altra, un’analisi dei mutamenti degli equilibri esistenziali – lavorativi, familiari e nelle relazioni sociali – che si registrano dopo l’uscita dalla fabbrica.
Poro_Thermoelastic Duality and FE-based strategies for the analysis of biological tissues
Creators: name: Capone, Claudia Cristiana Chiara
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2010

description: Many analytical and numerical approaches have been proposed in order to solve poroelastic problems describing the behavior of biological tissues. The main difficulty associated to numerical strategies concerns the solution of the coupled poroelastic equations for determining the solid response in terms of deformation and filtration. The proposal of this work is to find a strategy to numerically solve poroelastic problems employing the Finite Element Method (FEM). In particular, the strategy presented is based on the well known similarity between thermoelasticity and poroelasticity theories. This analogy allows to solve transient poroelastic problems as corresponding thermoelastic ones, interpreting the temperature as a pressure and thermal gradients as velocities. With this aim, the relationship between thermoelasticity and poroelasticity is formulated in terms of dimensionless parameters to ensure numerical stability, because the elasticity moduli, filtration coefficients and porosity have essentially different orders of magnitude. Thus, the dimensionless equations obtained are implemented in numerical FEM-based computations. Such transferring to equivalent thermoelastic problems enables to apply the FEM package ANSYS® 11, which provides opportunities to solve coupled thermoelastic problems in transient non linear settings. Two numerical examples are finally presented. The first one is concerning a very important problem of drug delivery in solid tumors. The second example is, instead, related to the investigation of the role played by trigonal-like microstructure in osteons in bone adaptive, growth and remodeling processes.
Diffusion-weighted MRI 3T nella valutazione di pazienti con carcinoma dell'endometrio e della cervice uterina: confronto con FDG PET-TC con mezzo di contrasto iodato
Creators: name: Pizzuti, Laura Micol
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2010

description: In questo studio ho valutato 40 pazienti con carcinoma dell'endometrio e della cervice uterina sottoponendole ad esame RM con mdc ev (gadolinio) con l'aggiunta di sequenze di diffusione (DWI) ed ad esame PET-TC con mdc iodato. Ho poi dimostrato la correlazione tra i valori delle mappe di ADCmin., che si ottengono dalle sequenze DWI ed i valori delle SUVmax che misurano l'iperaccumulo di FDG nel sito tumorale. Nel lavoro ho notato una correlazione inversa che esiste tra questi due parametri che risultano inversamente correlati, ossia all'aumentare del valore di SUVmax diminuiva il valore di ADCmin. Inoltre, a bassi valori di ADC corrispondeva un alto grading del tumore.
Molecular genetic approaches to the study of early sex determination in the Mediterranean fruit fly Ceratitis capitata
Creators: name: Zhang, Ying
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2010

description: In Ceratitis capitata, noto dittero dannoso all’agricoltura, la determinazione del sesso è controllata da un gene chiave, Cctransformer (Cctra) che durante l’embriogenesi è attivo negli embrioni XX e viene spento a 8-10 ore negli XY grazie all’attività del fattore M Y-linked, determinante la mascolinità. Il gene Cctra negli embrioni XX codifica una proteina che regola lo splicing dei pre-mRNA sia del medesimo Cctra, che di Ccdoublesex e Ccfruitless, (Ccdsx di Ccfru). Negli embrioni XY i trascritti maschio-specifici di Cctra codificano per una proteina tronca non funzionale, e Ccdsx e Ccfru, producono trascritti alternativi, codificanti isoforme proteiche maschio-specifiche, che agiscono come fattori trascrizionali di geni bersaglio coinvolti nel controllo del differenziamento sessuale visibile a stadio adulto della mosca. In Drosophila melanogaster il differente segnale primario per la determinazione del sesso, che consiste nel numero di cromosomi X (2X nelle femmine e un X nei maschi) agisce invece sul gene Sex-lethal, che a sua volta agisce sul gene transformer, il quale controlla lo splicing dei geni doublesex e fruitless. La cascata regolativa di Drosophila è quindi parzialmente conservata in Ceratitis. Il progetto di tesi di dottorato è stato focalizzato sulla identificazione di geni di Ceratitis che abbiano espressione maschio-specifica o maggiore nei maschi XY a stadi embrionali precoci dello sviluppo. Questo studio sperimentale è stato condotto al fine di identificare il gene M Y-linked e chiarire quindi come funziona l’inizio della determinazione del sesso in Ceratitis, ma anche al fine di isolare altri geni che collaborino con M, o che siano regolati da M, durante l’embriogenesi delgi XY. Abbiamo identificato il primo gene Y-linked in Ceratitis che risulta essere trascrizionalmente attivo a stadi precoci dell’embriogenesi (1-2 ore dalla ovodeposizione) e ne abbiamo iniziato a studiare le regioni promotrici. Abbiamo condotto esperimenti di sottrazione molecolare e in tal modo abbiamo identificato 11 geni di Ceratitis che risultano maggiormente espressi in embrioni XY rispetto agli XX ad 8-10 dalla ovodeposizione.
Performance Evaluation of DG in Distribution System: An Extensive Review
Creators: name: Gaurav Chauhan, Sakshi Bangia
Publisher: name: TuEngr Group
Year: 2021
Subjects: Distributed Generation
Energy efficiency
Power loss
Power network
DG optimal placement and sizing (OPaS)
Fault Current Limiters (FCL)
Particle Swarm Optimization (PSO), Genetic Algorithm (GA).

description: International Transaction Journal of Engineering, Management, & Applied Sciences & Technologies, 12, 2, 12A2I: 1-11
Codeword Stabilized Quantum Codes
Creators: name: Cross, Andrew
name: Smith, Graeme
name: Smolin, John A.
name: Zeng, Bei
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present a unifying approach to quantum error correcting code design that encompasses additive (stabilizer) codes, as well as all known examples of nonadditive codes with good parameters. We use this framework to generate new codes with superior parameters to any previously known. In particular, we find ((10,18,3)) and ((10,20,3)) codes. We also show how to construct encoding circuits for all codes within our framework.
description: 5 pages, 1 eps figure, ((11,48,3)) code removed, encoding circuits added, typos corrected in codewords and elsewhere
The Global 21 cm Signal of a Network of Cosmic String Wakes
Creators: name: Hernández, Oscar F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In previous works we discussed the 21 cm signature of a single cosmic string wake. However the 21 cm brightness temperature is influenced by a network of cosmic string wakes, and not one single wake. In this work we consider the signal from a network of wakes laid down during the matter era. We also improve on the previous calculation of a single wake signature. Finally we calculate the enhancement of the global 21 cm brightness temperature due to a network of wakes and discuss its affects of the signal measured in the Wouthuysen-Field absorption trough. We estimated that for string tensions between $10^{-8}$ to $10^{-7}$ there would be between a 10% to a factor 2 enhancement in the signal.
description: 6 pages, 4 figure. v2 to v3: minor typo corrected in references. v1 to v2: explanation in section 5 expanded, figures enlarged, NANOGrav data description changed in section 2, 1 references added in section 2. Matches the version accepted for publication by MNRAS
Getting More For Your Money: Identifying and Confirming Long-Period Planets with Kepler
Creators: name: Yee, Jennifer C.
name: Gaudi, B. Scott
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Kepler will monitor enough stars that it is likely to detect single transits of planets with periods longer than the mission lifetime. We show that by combining the Kepler photometry of such transits with precise radial velocity (RV) observations taken over ~3 months, and assuming circular orbits, it is possible to estimate the periods of these transiting planets to better than 20% (for planets with radii greater than that of Neptune) and the masses to within a factor of 2 (for planet masses m_p > M_Jup). We also explore the effects of eccentricity on our estimates of these uncertainties.
description: 4 pages, 4 figures, Proceedings of IAU Symposium 253: Transiting Planets
A generalized Haus master equation model for mode-locked class-B lasers
Creators: name: Nizette, Michel
name: Vladimirov, Andrei G.
Publisher: name: Weierstrass Institute
Year: 2021
Subjects: subject: Haus master equation
subject: mode-locking
subject: class B laser
subject: multiscale method
subject: 37N20
subject: 78M34
subject: 78M35
subject: 42.65.-k
subject: 42.65.R
subject: 42.60.F
subject: 42.60.G

description: Using the multiscale technique we develop a generalized version of the class-B Haus modelocking model that accounts for both the slow gain response to the averaged value of the field intensity and the fast gain dynamics on the scale comparable to the pulse duration. We show that unlike the standard class-B Haus mode-locked model, our model is able to describe not only Q-switched instability of the fundamental mode-locked regime, but also the appearance of harmonic mode-locked regimes with the increase of the pump power.
The Detectability of Neon Fluorescence and Measurement of the Solar Photospheric Neon Abundance
Creators: name: Drake, Jeremy J.
name: Ercolano, Barbara
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Monte Carlo calculations of the Ne K$α$ line fluoresced by coronal x-rays and emitted near the temperature minimum region of the solar atmosphere have been employed to investigate the use of this feature to measure directly the solar photospheric Ne abundance. Though very weak, comparison with spectral line databases indicates that at plasma temperatures typical of the quiet Sun and cool active regions ($\leq 2\times 10^6$ K) the line is isolated and unblended. A canonical solar chemical composition yields an equivalent width of $\sim 6$ mÅ(0.3 eV) when observed at heliocentric angles $\sim 0$. For a 1 arcmin field of view, photon fluxes at Earth are of order 0.2 ph s$^{-1}$ for the quiet Sun, rendering the Ne K$α$ fluorescent line a quite feasible means for determining the solar photospheric Ne content.
description: To appear in Astrophysical Journal Letters. 13 pages, 3 figures, 1 table
Understanding Segmental Dynamics in Polymer Electrolytes: A Computer Study
Creators: name: Maitra, Arijit
name: Heuer, Andreas
Publisher: name: arXiv
Year: 2008
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We study the segmental dynamics of poly(ethylene oxide) (PEO) from microscopic simulations in the neat polymer and a polymer electrolyte (PEO/LiBF$_4$) by analyzing the normal modes. We verify the applicability of the Rouse theory, specifically for the polymer electrolyte where dynamic heterogeneities, arising from cation-polymer interactions, alter the mobility non-uniformly along the chains. We find that the Rouse modes for both the systems are orthogonal despite the presence of non-exponential relaxation of the modes and violation of the Gaussian self-similarity of the chains. The slowdown of the segmental dynamics in the polymer electrolyte is rationalised by an order of magnitude increase in the friction coefficient for those monomers which are bound by cations. In general, for the electrolyte the Rouse predictions for the dynamics of segments (both free and/or bound) agree well except for very short times.
The Barbero-Immirzi Parameter as a Scalar Field: K-Inflation from Loop Quantum Gravity?
Creators: name: Taveras, Victor
name: Yunes, Nicolas
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a loop-quantum gravity inspired modification of general relativity, where the Holst action is generalized by making the Barbero-Immirzi (BI) parameter a scalar field, whose value could be dynamically determined. The modified theory leads to a non-zero torsion tensor that corrects the field equations through quadratic first-derivatives of the BI field. Such a correction is equivalent to general relativity in the presence of a scalar field with non-trivial kinetic energy. This stress-energy of this field is automatically covariantly conserved by its own dynamical equations of motion, thus satisfying the strong equivalence principle. Every general relativistic solution remains a solution to the modified theory for any constant value of the BI field. For arbitrary time-varying BI fields, a study of cosmological solutions reduces the scalar field stress-energy to that of a pressureless perfect fluid in a comoving reference frame, forcing the scale factor dynamics to be equivalent to those of a stiff equation of state. Upon ultraviolet completion, this model could provide a natural mechanism for k-inflation, where the role of the inflaton is played by the BI field and inflation is driven by its non-trivial kinetic energy instead of a potential.
description: Phys. Rev. D78, 064070 (2008)
Groot: An Event-graph-based Approach for Root Cause Analysis in Industrial Settings
Creators: name: Wang, Hanzhang
name: Wu, Zhengkai
name: Jiang, Huai
name: Huang, Yichao
name: Wang, Jiamu
name: Kopru, Selcuk
name: Xie, Tao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: For large-scale distributed systems, it's crucial to efficiently diagnose the root causes of incidents to maintain high system availability. The recent development of microservice architecture brings three major challenges (i.e., operation, system scale, and monitoring complexities) to root cause analysis (RCA) in industrial settings. To tackle these challenges, in this paper, we present Groot, an event-graph-based approach for RCA. Groot constructs a real-time causality graph based on events that summarize various types of metrics, logs, and activities in the system under analysis. Moreover, to incorporate domain knowledge from site reliability engineering (SRE) engineers, Groot can be customized with user-defined events and domain-specific rules. Currently, Groot supports RCA among 5,000 real production services and is actively used by the SRE teamin a global e-commerce system serving more than 185 million active buyers per year. Over 15 months, we collect a data setcontaining labeled root causes of 952 real production incidents for evaluation. The evaluation results show that Groot is able to achieve 95% top-3 accuracy and 78% top-1 accuracy. To share our experience in deploying and adopting RCA in industrial settings, we conduct survey to show that users of Grootfindit helpful and easy to use. We also share the lessons learnedfrom deploying and adopting Grootto solve RCA problems inproduction environments.
Quaternionic Kahler Manifolds, Constrained Instantons and the Magic Square: I
Creators: name: Dasgupta, Keshav
name: Hussin, Veronique
name: Wissanji, Alisha
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The classification of homogeneous quaternionic manifolds has been done by Alekseevskii, Wolf et al using transitive solvable group of isometries. These manifolds are not generically symmetric, but there is a subset of quaternionic manifolds that are symmetric and Einstein. A further subset of these manifolds are the magic square manifolds. We show that all the symmetric quaternionic manifolds including the magic square can be succinctly classified by constrained instantons. These instantons are mostly semilocal, and their constructions for the magic square can be done from the corresponding Seiberg-Witten curves for certain N = 2 gauge theories that are in general not asymptotically free. Using these, we give possible constructions, such as the classical moduli space metrics, of constrained instantons with exceptional global symmetries. We also discuss the possibility of realising the Kahler manifolds in the magic square using other solitonic configurations in the theory, and point out an interesting new sequence of these manifolds in the magic square.
description: Harvmac, 66 pages, 9 .eps figures; v2: Three new results added around pages 15, 50 and 51, typos corrected and references added; v3: Some more typos corrected. Final version to appear in Nuclear Physics B
Mott-Insulator Transition for Ultracold Fermions in Two-Dimensional Optical Lattices
Creators: name: Goldman, N.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: In this work we study ultracold Fermions confined in a two-dimensional optical lattice and we explore the Mott-insulator transition with the Fermi-Hubbard model. On the basis of a mean-field approach, we study the phase diagrams in the presence of a harmonic trapping potential. Local Mott-insulator phases are shown to be generally situated in the center of the trap and correspond to a vanishing variance of the local density. We then study the effects induced by rotation on the Mott-insulator phase transition. In particular, we show that the phase boundary reproduces the edge of the Hofstadter butterfly.
description: 7 pages, 7 figures, to appear in Physical Review A
Correlation versus randomization of jerky flow in an AlMgScZr alloy using acoustic emission
Creators: name: Lebedkina, T. A.
name: Zhemchuzhnikova, D. A.
name: Lebyodkin, M. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: Jerky flow in solids results from collective dynamics of dislocations which gives rise to serrated deformation curves and a complex evolution of the strain heterogeneity. A rich example of this phenomenon is the Portevin-Le Chatelier effect in alloys. The corresponding spatiotemporal patterns showed some universal features which provided a basis for a well-known phenomenological classification. Recent studies revealed peculiar features in both the stress serration sequences and the kinematics of deformation bands in Al-based alloys containing fine microstructure elements, such as nanosize precipitates and (or) submicron grains. In the present work, jerky flow of an AlMgScZr alloy is studied using statistical analysis of stress serrations and the accompanying acoustic emission. As in the case of coarse-grained binary AlMg alloys, the amplitude distributions of acoustic events obey a power-law scaling which is usually considered as evidence of avalanchelike dynamics. However, the scaling exponents display specific dependences on the strain and strain rate for the investigated materials. The observed effects bear evidence to a competition between the phenomena of synchronization and randomization of dislocation avalanches, which may shed light on the mechanisms leading to a high variety of jerky flow patterns observed in applied alloys.
description: 13 pages, 6 figures, 1 table
Non-thermal emission in the core of Perseus: results from a long XMM-Newton observation
Creators: name: Molendi, Silvano
name: Gastaldello, Fabio
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We employ a long XMM-Newton observation of the core of the Perseus cluster to validate claims of a non-thermal component discovered with Chandra. From a meticulous analysis of our dataset, which includes a detailed treatment of systematic errors, we find the 2-10 keV surface brightness of the non-thermal component to be smaller than about 5x10^-16 erg cm^-2s^-1arcsec^-2. The most likely explanation for the discrepancy between the XMM-Newton and Chandra estimates is a problem in the effective area calibration of the latter. Our EPIC based magnetic field lower limits are not in disagreement with Faraday rotation measure estimates on a few cool cores and with a minimum energy estimate on Perseus. In the not too distant future Simbol-X may allow detection of non-thermal components with intensities more than 10 times smaller than those that can be measured with EPIC; nonetheless even the exquisite sensitivity within reach for Simbol-X might be insufficient to detect the IC emission from Perseus.
description: To appear in A&A main Journal
Neutron star magnetospheres: the binary pulsar, Crab and magnetars
Creators: name: Lyutikov, Maxim
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: A number of disparate observational and theoretical pieces of evidence indicate that, contrary to the conventional wisdom, neutron stars' closed field lines are populated by dense, hot plasma and may be responsible for producing some radio and high energy emission. This conclusion is based on eclipse modeling of the binary pulsar system PSR J0737-3039A/B (Lyutikov & Thompson 2005), a quantitative theory of Crab giant pulses (Lyutikov 2007) and a number of theoretical works related to production of non-thermal spectra in magnetars through resonant scattering. In magnetars, dense pair plasma is produced by twisting magnetic field lines and associated electric fields required to lift the particles from the surface. In long period pulsars, hot particles on closed field lines can be efficiently trapped by magnetic mirroring, so that relatively low supply rate, e.g. due to a drift from open field lines, may result in high density. In short period pulsars, magnetic mirroring does not work; large densities may still be expected at the magnetic equator near the Y-point.
description: Proceedings, Huangshan meeting "Astrophysics of Compact Objects"
La 3,5 diiodo-l-tironina, obesità e steatosi epatica: focus sulla funzionalità mitocondriale
Creators: name: Gifuni, Giorgio
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2010

description: L’obesità è la più frequente disfunzione nutrizionale nel mondo; col termine obesità si intende un aumento di peso corporeo per accumulo di grassi nel tessuto adiposo in quantità eccessiva rispetto alle necessità fisiologiche dell’organismo tale da determinare un rischio per la salute.
Tra le principali conseguenze metaboliche dell’obesità troviamo la steatosi epatica e l’insulino-resistenza.I mitocondri, la centrale del metabolismo energetico cellulare, sembrano essere coinvolti nello sviluppo delle patologie associate all’obesità, quali appunto, steatosi epatica e insulino-resistenza. Infatti diversi studi hanno dimostrato che disfunzioni mitocondriali e stress ossidativo sono meccanismi alla base dello sviluppo di tali patologie.
 Nella terapia dell’obesità, per lungo tempo, sono stati utilizzati gli ormoni tiroidei, in particolare la triiodotironina o T3, per la sua capacità di incrementare la spesa energetica. In seguito l’utilizzo della T3 come farmaco anti-obesità è stato abolito per i suoi effetti tireotossici indesiderati (aumento della frequenza cardiaca, ipertrofia cardiaca, riduzione della massa magra, alterazione dell’asse ipotalamo-ipofisi-tiroide),
Negli ultimi anni, è stato dimostrato che la 3,5-diiodo-l-tironina (T2), una iodotironina naturalmente prodotta dalla tiroide, possiede attività biologiche simili a quelle della T3, ma indipendenti da essa e senza induzione dello stato tireotossico.
E’ evidente l’importanza della prevenzione e/o dell’intervento precoce in modo da arrestare o, quantomeno, far regredire lo sviluppo dell’obesità e delle patologie ad essa correlate, tramite lo studio di molecole biologicamente attive, come appunto, la T2: l’analisi è focalizzata soprattutto sull’effetto della T2 sulla funzionalità mitocondriale epatica tenendo presente il ruolo fondamentale di questi organelli cellulari nell’energetica cellulare e nello sviluppo della steatosi epatica.
Observation of Landau levels of Dirac fermions in graphite
Creators: name: Li, Guohong
name: Andrei, Eva Y.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The low energy electronic excitations in single layer and bilayer graphite (graphene) resemble quantum-relativistic particles also known as Dirac Fermions (DF). They possess an internal degree of freedom, chirality, that leads to unusual Landau Level (LL) energy sequences in a magnetic field and profoundly alters the magneto-transport properties. One of the consequences is an anomalous Quantum-Hall effect, recently detected in both single layer and bi-layer graphene. However the underlying cause, the unusual LL sequence, was never observed. Here we report the direct observation of LL of DF by means of low temperature Scanning-Tunnelling-Spectroscopy (STS) on the surface of graphite in fields up to 12 Tesla. We find evidence of coexistence of massless and massive DF, and identify the zero-energy LL which is a unique consequence of their quantum-relativistic nature. Surprisingly these strictly two-dimensional properties emerge even on bulk graphite in samples where the interlayer coupling is weak.
description: 14 pages, 4 figures. to appear in Nature Physics
Studio strutturale di materiali polimerici con fasi cristalline nanoporose e/o co-cristalline.
Creators: name: Schiavone, Maria Maddalena
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2010

description: Oggetto di questa tesi è stato lo studio di alcune fasi co-cristalline del polistirene sindiotattico (s-PS) e della sua forma nanoporosa epsilon; in particolare, il lavoro svolto ha riguardato principalmente la determinazione della struttura cristallina di nuovi co-cristalli del s-PS (alcuni dei quali ottenuti per la prima volta dalla forma nanoporosa epsilon) al fine di apportare un contributo alla comprensione più dettagliata della relazione proprietà-struttura che intercorre in questo tipo di materiali.
Some aspects of the economics of territoriality in North American hummingbirds
Creators: name: Armstrong, Doug P.
Publisher: name: University of British Columbia
Year: 2010

description: Territoriality of post-breeding North American hummingbirds is one of the clearest examples of energy-based feeding territoriality, and has played an important role in the formulation and testing of theories on territoriality. This thesis follows two lines of inquiry. First, what special foraging strategies are used by hummingbirds holding energy-based feeding territories? Second, are energy-based models applicable to territoriality of breeding as well as non-breeding hummingbirds? I use a simulation model to examine the possible benefits for a non-breeding territorial hummingbird of avoiding recently visited locations while foraging. The simulation results suggest that while birds might benefit by avoiding flowers visited recently during a foraging bout, they would not benefit significantly by avoiding patches of flowers visited on previous bouts. An important benefit of short-term avoidance of flowers for model birds is that they can empty all or nearly all flowers in each patch visited. They therefore create coarse-grained patterns of nectar availability that are easy to exploit later on. Results of a field study on breeding territoriality of male Calliope Hummingbirds indicate that a solely energy-based model of territoriality cannot account for the behavior of these males. Throughout the 2 month breeding season, flower sampling indicated that males could have obtained energy faster by foraging on nearby undefended areas than by foraging on their territories. During June, flowers blooming on the territories were sparse and/or contained very little nectar, and males could not have obtained enough energy from them even to compensate for the cost of hovering while foraging. Consequently, they did virtually all their foraging away from their territories at that time. During May, when nectar availability on the territories was at its peak, males did not leave, expand, or shift their territories in response to experimental exclosure of all flowers blooming on them. I develop a model of optimal territory size for a promiscuously breeding male that defends a breeding territory containing no energy sources, as did the Calliope males during June at my study site. This model is analogous in design to existing models of energy-based feeding territoriality, but is based on the premise that a male's optimal territory size is that which maximizes his immediate reproductive success. A prediction of this model is that a male's territory size will be limited by the rate at which he can obtain energy while foraging away from his territory. An experiment performed on a Calliope male's territory did not support this prediction, and suggested that the size of his territory may have been limited only by his ability to detect intruders.
Strongly Magnetized Hot QCD Matter and Stochastic Gravitational Wave Background
Creators: name: Khodadi, Mohsen
name: Dey, Ujjal Kumar
name: Lambiase, Gaetano
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The first-order phase transitions in the early Universe are one of the well-known sources which release the stochastic background of gravitational waves. In this paper, we study the contribution of an external static and strong magnetic field on the stochastic background of gravitational waves (GWs) expected during QCD phase transition. In the light of the strongly magnetized hot QCD equation of state which deviated from the ideal gas up to the one-loop approximation, we estimate two phenomenologically important quantities: peak frequency redshifted to today ($f_{\rm peak}$) and GW strain amplitude ($h^2 Ω_{gw}$). The trace anomaly induced by the magnetized hot QCD matter around the phase transition generates the stochastic background of GW with peak frequencies lower than the ideal gas-based signal (around nHz). Instead, the strain amplitudes corresponding to the peak frequencies are of the same order of magnitude of the expected signal from ideal gas. This may be promising in the sense that although the strong magnetic field could mask the expected stochastic background of GWs by upgrading the frequency sensitivity of detectors in the future, the magnetized GW is expected to be identified. Faced with the projected reach of detectors EPTA, IPTA, and SKA, we find that for the tail of the magnetized GW signals there remains a mild possibility of detection as it can reach the projected sensitivity of SKA.
description: 17 pages, 4 figures, to appear in PRD
Immobilization of single strand DNA on solid substrate
Creators: name: Hussain, Syed Arshad
name: Paul, P. K.
name: Dey, D.
name: Bhattacharjee, D.
name: Sinha, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Thin films based on Layer-by-Layer (LbL) self assembled technique are useful for immobilization of DNA onto solid support. This communication reports the immobilization of DNA onto a solid support by electrostatic interaction with a polycation Poly (allylamine hydrochloride) (PAH). UV-Vis absorption and steady state fluorescence spectroscopic studies exhibit the characteristics of DNA organized in LbL films. The most significant observation is that single strand DNA are immobilized on the PAH backbone of LbL films when the films are fabricated above the melting temperature of DNA. DNA immobilized in this way on LbL films remains as such when the temperature is restored at room temperature and the organization remains unaffected even after several days. UV-Vis absorption spectroscopic studies confirm this finding.
description: Eight pages, five figures
The colour scheme of the Munich Olympic Games 1972. From concept to materials
Creators: name: Sessa, Clarimma
name: Steuer, Christoph
name: Stege, Heike
name: Danzl, Thomas
Publisher: name: ICOMOS – Hefte des Deutschen Nationalkomitees
Year: 2021

description: ICOMOS – Hefte des Deutschen Nationalkomitees, Bd. 76 (2020): ICOMOS – Hefte des Deutschen Nationalkomitees