Critical behavior of density of states near Fermi energy in low-dimensional disordered metals

We study the effect of electron-electron interaction on the one-particle density of states (\emph{DOS}) $\rho^{(d)}(\epsilon,T)$ of low-dimensional disordered metals near Fermi energy within the framework of the finite temperature conventional impurity diagram technique. We consider only diffusive limit and by a geometric re-summation of the most singular first order self-energy corrections via the Dyson equation we obtain a non-divergent solution for the \emph{DOS} at low energies, while for higher energies the well-known Altshuler-Aronov corrections are recovered. At the Fermi level $\rho^{(d)}(\epsilon,T=0)\to 0$, this indicates that interacting disordered two- and quasi-one-dimensional systems are in insulating state at zero temperature. The obtained results are in good agreement with recent tunneling experiments on two-dimensional GaAs/AlGaAs heterostructures and quasi-one-dimensional doped multiwall carbon nanotubes.Comment: 8 pages, 4 figure

Subtracting Compact Binary Foregrounds to Search for Subdominant Gravitational-Wave Backgrounds in Next-Generation Ground-Based Observatories

Stochastic gravitational-wave backgrounds (SGWBs) derive from the superposition of numerous individually unresolved gravitational-wave (GW) signals. Detecting SGWBs provides us with invaluable information about astrophysics, cosmology, and fundamental physics. In this paper, we study SGWBs from binary black-hole (BBH) and binary neutron-star (BNS) coalescences in a network of next-generation ground-based GW observatories (Cosmic Explorer and Einstein Telescope) and determine how well they can be measured; this then limits how well we can observe other subdominant astrophysical and cosmological SGWBs. We simulate all-Universe populations of BBHs and BNSs and calculate the corresponding SGWBs, which consist of a superposition of (i) undetected signals, and (ii) the residual background from imperfect removal of resolved sources. The sum of the two components sets the sensitivity for observing other SGWBs. Our results show that, even with next-generation observatories, the residual background is large and limits the sensitivity to other SGWBs. The main contributions to the residual background arise from uncertainties in inferring the coalescence phase and luminosity distance of the detected signals. Alternative approaches to signal subtraction would need to be explored to minimize the BBH and BNS foreground in order to observe SGWBs from other subdominant astrophysical and cosmological sources.Comment: 19 pages, 10 figures, matches the published versio

The novel benzimidazole derivative BRP-7 inhibits leukotriene biosynthesis in vitro and in vivo by targeting 5-lipoxygenase-activating protein (FLAP).

BACKGROUND AND PURPOSE: Leukotrienes (LTs) are inflammatory mediators produced via the 5-lipoxygenase (5-LOX) pathway and are linked to diverse disorders, including asthma, allergic rhinitis and cardiovascular diseases. We recently identified the benzimidazole derivative BRP-7 as chemotype for anti-LT agents by virtual screening targeting 5-LOX-activating protein (FLAP). Here, we aimed to reveal the in vitro and in vivo pharmacology of BRP-7 as an inhibitor of LT biosynthesis. EXPERIMENTAL APPROACH: We analysed LT formation and performed mechanistic studies in human neutrophils and monocytes, in human whole blood (HWB) and in cell-free assays. The effectiveness of BRP-7 in vivo was evaluated in rat carrageenan-induced pleurisy and mouse zymosan-induced peritonitis. KEY RESULTS: BRP-7 potently suppressed LT formation in neutrophils and monocytes and this was accompanied by impaired 5-LOX co-localization with FLAP. Neither the cellular viability nor the activity of 5-LOX in cell-free assays was affected by BRP-7, indicating that a functional FLAP is needed for BRP-7 to inhibit LTs, and FLAP bound to BRP-7 linked to a solid matrix. Compared with the FLAP inhibitor MK-886, BRP-7 did not significantly inhibit COX-1 or microsomal prostaglandin E2 synthase-1, implying the selectivity of BRP-7 for FLAP. Finally, BRP-7 was effective in HWB and impaired inflammation in vivo, in rat pleurisy and mouse peritonitis, along with reducing LT levels. CONCLUSIONS AND IMPLICATIONS: BRP-7 potently suppresses LT biosynthesis by interacting with FLAP and exhibits anti-inflammatory effectiveness in vivo, with promising potential for further development

Performative Work: Bridging Performativity and Institutional Theory in the Responsible Investment Field

Callon’s performativity thesis has illuminated how economic theories and calculative devices shape markets, but has been challenged for its neglect of the organizational, institutional and political context. Our seven-year qualitative study of a large financial data company found that the company’s initial attempt to change the responsible investment field through a performative approach failed because of the constraints posed by field practices and organizational norms on the design of the calculative device. However, the company was subsequently able to put in place another form of performativity by attending to the normative and regulative associations of the device. We theorize this route to performativity by proposing the concept of performative work, which designates the necessary institutional work to enable translation and the subsequent adoption of the device. We conclude by considering the implications of performative work for the performativity and the institutional work literatures

Composing Urban Orders from Rubbish Electronics: Cityness and the Site Multiple

What do cities look like when rubbish electronics are the vehicle with which they are explored? This article is an experiment designed to offer a response to that question, and in doing so to productively intervene in the conversation about ‘cityness’, ‘metrocentricity’ and ‘subaltern urbanism’. We intervene by following flows of rubbish electronics and the action that enacts them as waste and value, drawing on fieldwork in Dhaka, Singapore, Accra and Canada’s Greater Golden Horseshoe. Our intervention is an experiment in writing an urban geography of rubbish electronics as a site multiple. We show how following the circulation of rubbish electronics offers a many-folded synopsis of cities: urban enclaves of high finance and the information economy are also industrial waste producers. Peri-urban industrial zones are also managers of brands, legal liability and corporate public relations. Cities off the map are also urban innovation systems, while waste is rekindled as value and accumulated as poison. Thereby we suggest how a sensitivity to the site multiple may be a helpful way of grappling with shifting ontology and the performativity of our research practices in urban studies

Physical Parameters of Some Close Binaries: ET Boo, V1123 Tau, V1191 Cyg, V1073 Cyg and V357 Peg

With the aim of providing new and up-to-date absolute parameters of some close binary systems, new BVR CCD photometry was carried out at the Ankara University Observatory (AUG) for five eclipsing binaries, ET Boo, V1123 Tau, V1191 Cyg, V1073 Cyg and V357 Peg between April, 2007 and October, 2008. In this paper, we present the orbital solutions for these systems obtained by simultaneous light and radial velocity curve analyses. Extensive orbital solution and absolute parameters for ET Boo system were given for the first time through this study. According to the analyses, ET Boo is a detached binary while the parameters of four remaining systems are consistent with the nature of contact binaries. The evolutionary status of the components of these systems are also discussed by referring to their absolute parameters found in this study.Comment: this accepted paper will be published in New Astronom

Cosmology with the Laser Interferometer Space Antenna

The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational wave observations by LISA to probe the universe

Karın duvarında nekrotizan fasiite neden olmuş Amyand herni

Amyand’s hernia is a rare clinical condition and is defined as the presence of the appendix vermiformis in the hernia sac. The appendix found in the hernia sac might be normal, inflamed, perforated or incarcerated. Clinically, Amyand’s hernia, and the inflammation of the appendix due to it, may be confused with a strangulated or incarcerated hernia. Because symptoms of the incarcere hernia can mask the symptoms of acute appendicitis, preoperative diagnosis is somewhat difficult. An inflamed appendix in the hernia sac can be detected only by opening the hernia sac. Ultrasound and computed tomography are used efficiently in diagnosis. Treatment is surgical and the most appropriate method is appendectomy and hernia repair through an inguinal incision. In this case report, we aimed to present a patient who was operated on prediagnosed as a incarcerated inguinal hernia, and peroperatively diagnosed as having Amyand’s hernia causing necrotizing fasciitis of the abdominal wall.Amyand herni, nadir görülen bir klinik durum olup, apendiks vermiformisin fıtık kesesi içinde bulunması olarak tanımlanır. Apendiks fıtık kesesi içinde normal, inflame, perfore ya da inkarsere şekilde bulunabilir. Klinik olarak Amyand herni ve buna bağlı apendiks inflamasyonu strangüle ya da inkarsere herni ile karışabilmektedir. İnkarsere herni kliniği akut apandisit kliniğini maskelediğinden preoperatif tanı konulması güçtür. Fıtık kesesi içinde inflame apendiks ancak fıtık kesesi açılarak tespit edilebilir. Tanıda ultrasonografi ve bilgisayarlı tomografi (BT) etkin olarak kullanılan yöntemlerdir. Tedavi cerrahidir ve ingüinal kesi ile apendektomi ve herni tamiri en uygun yöntemdir. Bu olgu sunumunda inkarsere ingüinal herni tanısıyla opere edilen ve operasyonda karın duvarında nekrotizan fasiite neden olmuş Amyand herni tanısı alan olgunun sunulması amaçlandı

Apical microleakage of root-end cavities prepared by Er, Cr: YSGG laser

PubMed ID: 19277818The aim of this study is to assess the apical microleakage of the composite filled root-end cavities prepared by an Erbium, Chromium: Yttrium-Scandium- Gallium-Garnet laser. Fifty-five maxillary incisor teeth were enlarged and filled. Following the apical resection, root-end cavities were prepared using conventional methods: Either using a bur (n = 30) or an ultrasonic retrotip (n = 15). Root-end cavities of the 15 teeth in the bur group were finished with the laser at 3.5 W. All root-end cavities were filled using two-step self-etching primer and composite resin. After 4 months of storage, apical microleakage was measured by a fluid filtration method. Microleakage of composite filled root-end cavities that were prepared by Er, Cr: YSGG was significantly larger than those made by conventional methods (p < 0.05). In conclusion, using the Er, Cr: YSGG laser has no advantages over conventional root-end cavity preparation methods when a composite filling material is used to seal root-end cavities. © 2009 Springer-Verlag London Ltd