Determination of the top-quark pole mass using t(t)over-bar+1-jet events collected with the ATLAS experiment in 7 TeV pp collisions

The normalized differential cross section for top-quark pair production in association with at least one jet is studied as a function of the inverse of the invariant mass of the tt¯+1-jet system. This distribution can be used for a precise determination of the top-quark mass since gluon radiation depends on the mass of the quarks. The experimental analysis is based on proton--proton collision data collected by the ATLAS detector at the LHC with a centre-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.6 fb−1. The selected events were identified using the lepton+jets top-quark-pair decay channel, where lepton refers to either an electron or a muon. The observed distribution is compared to a theoretical prediction at next-to-leading-order accuracy in quantum chromodynamics using the pole-mass scheme. With this method, the measured value of the top-quark pole mass, mpolet, is: mpolet =173.7 ± 1.5 (stat.) ± 1.4 (syst.) +1.0−0.5 (theory) GeV. This result represents the most precise measurement of the top-quark pole mass to date.

Differential activation of the default mode network in jet lagged individuals

Long-term exposure to transmeridian flights has been shown to impact cognitive functioning. Nevertheless, the immediate effects of jet lag in the activation of specific brain networks have not been investigated. We analyzed the impact of short-term jet lag on the activation of the default mode network (DMN). A group of individuals who were on a transmeridian flight and a control group went through a functional magnetic resonance imaging acquisition. Statistical analysis was performed to test for differences in the DMN activation between groups. Participants from the jet lag group presented decreased activation in the anterior nodes of the DMN, specifically in bilateral medial prefrontal and anterior cingulate cortex. No areas of increased activation were observed for the jet lag group. These results may be suggestive of a negative impact of jet lag on important cognitive functions such as introspection, emotional regulation and decision making in a few days after individuals arrive at their destination.

Erratum to: Measurement of the inclusive jet cross-section in proton-proton collisions at s√=7 TeV using 4.5 fb−1 of data with the ATLAS detector

It was found that the non-perturbative corrections calculated using Pythia with the Perugia 2011 tune did not include the effect of the underlying event. The affected correction factors were recomputed using the Pythia 6.427 generator. These corrections are applied as baseline to the NLO pQCD calculations and thus the central values of the theoretical predictions have changed by a few percent with the new corrections. This has a minor impact on the agreement between the data and the theoretical predictions. Figures 2 and 6 to 13, and all the tables have been updated with the new values. A few sentences in the discussion in sections 5.2 and 9 were altered or removed.

Measurement of transverse energy-energy correlations in multi-jet events in pp collisions at s√=7 TeV using the ATLAS detector and determination of the strong coupling constant αs(mZ)

High transverse momentum jets produced in pp collisions at a centre of mass energy of 7 TeV are used to measure the transverse energy--energy correlation function and its associated azimuthal asymmetry. The data were recorded with the ATLAS detector at the LHC in the year 2011 and correspond to an integrated luminosity of 158 pb−1. The selection criteria demand the average transverse momentum of the two leading jets in an event to be larger than 250 GeV. The data at detector level are well described by Monte Carlo event generators. They are unfolded to the particle level and compared with theoretical calculations at next-to-leading-order accuracy. The agreement between data and theory is good and provides a precision test of perturbative Quantum Chromodynamics at large momentum transfers. From this comparison, the strong coupling constant given at the Z boson mass is determined to be αs(mZ)=0.1173±0.0010 (exp.) +0.0065−0.0026 (theo.).

Measurement of colour flow with the jet pull angle in t(t)over-bar events using the ATLAS detector at root s=8 TeV

The distribution and orientation of energy inside jets is predicted to be an experimental handle on colour connections between the hard--scatter quarks and gluons initiating the jets. This Letter presents a measurement of the distribution of one such variable, the jet pull angle. The pull angle is measured for jets produced in tt¯ events with one W boson decaying leptonically and the other decaying to jets using 20.3 fb−1 of data recorded with the ATLAS detector at a centre--of--mass energy of s√=8 TeV at the LHC. The jet pull angle distribution is corrected for detector resolution and acceptance effects and is compared to various models.

Mecanismos de Fotopercepción No-Visual y Control Circadiano en la Retina Interna de Vertebrados en Condiciones Fisiológicas y en un Modelo Animal de Ceguera. Mechanisms of Non-visual Perception and Circadian Control in the Vertebrate Inner Retina under Physiological Conditions and in Animal Model of Blindness.

La retina juega un rol esencial en el funcionamiento del sistema circadiano de los vertebrados al ser la encargada de sensar las condiciones de iluminación ambiental que ajustan el reloj interno con el fotoperíodo exterior a través de un circuito no-visual. Este circuito es independiente de la vía de formación de imágenes e involucra a las células ganglionares retinianas (CGRs) que proyectan a varias estructuras no-visuales del cerebro; esta vía es la encargada de regular el reflejo pupilar, la sincronización de los ritmos diarios de actividad, el sueño y la supresión de melatonina pineal. La retina contiene además un reloj autónomo que genera ritmos diarios autosostenidos en distintas funciones bioquímicas y fisiológicas, que le confiere la capacidad de predecir el tiempo y anticiparse en su fisiología a los cambios lumínicos a lo largo del ciclo día-noche. Este laboratorio ha demostrado por 1ra vez que las CGRs de pollo poseen osciladores endógenos que generan variaciones diarias en la biosíntesis de fosfolípidos (Guido et al, J Neurochem. 2001; Garbarino et al., J Neurosci Res. 2004a) y de la hormona melatonina con niveles máximos durante el día (Garbarino et al., J Biol Chem 2004b). Aún más, cultivos primarios de CGRs responden a la luz a través de una cascada bioquímica de fototransducción similar a la de invertebrados y que involucra la activación de la enzima fosfolipasa C (PLC) (Contin et al., FASEB J 2006). Estos cultivos fueron obtenidos a estadios embrionarios muy tempranos en dónde solo las CGRs son postmitóticas y mayoritariamente maduras. A estos estadios, los cultivos expresan marcadores de especificación de células ganglionares (pax6, brn3), la proteina Gq y los fotopigmentos melanopsina y criptocromos con gran homología con marcadores descriptos para fotorreceptores rabdoméricos de invertebrados (Contin et al, 2006). Recientemente comenzamos a investigar la percepción de luz en pollos GUCY1*, un modelo de ceguera, en animales que carecen de células fotorreceptoras-conos y bastones-funcionales. Resultados preliminares indicarían que la retina interna, y potencialmente las CGRs de estos animales conservarían la capacidad de responder a la luz regulando el reflejo pupilar y sincronizando los ritmos diarios de alimentación. La convergencia de osciladores y fotopigmentos en la población de CGRs podría contribuir al control temporal de la fisiología del organismo y regulación de funciones no-visuales. Son objetivos de este proyecto: a) Investigar el rol de las CGRs en el sistema circadiano estudiando: i- su habilidad para sintetizar melatonina y, su regulación por luz y dopamina; ii- su capacidad fotorreceptora intrínseca, investigando la presencia de fotopigmentos y componentes de la cascada de fototransducción fundamentalmente la vía de los fosfoinosítidos y la activación de PLC, mediante ensayos moleculares, bioquímicos y farmacológicos; b) Extender estos estudios a cultivos primarios de CGRs inmunopurificadas midiendo la respuesta a la luz sobre la síntesis de melatonina, y los niveles de los mensajeros 2rios Ca2+ y AMP cíclico, la inducción de genes tempranos y la regulación de la actividad NAT, enzima clave en la síntesis de melatonina; y c) Investigar la percepción de luz en pollos GUCY1*(ciegos), sobre distintas funciones no-visuales tales como el reflejo pupilar, la sincronización de los ritmos diarios de alimentación, la síntesis de melatonina y la expresión génica en animales expuestos a estimulación lumínica de distintas intensidades y longitudes de onda. Estos estudios permitirán construir el espectro de acción de la respuesta a la luz en los pollos ciegos a fin de identificar el/los fotopigmentos intervinientes en este fenómeno. Este proyecto profundizará el conocimiento sobre la capacidad fotorreceptora-no visual de la retina interna y particularmente de las CGRs, de la naturaleza de la cascada bioquímica que opera en las mismas y de los mecanismos de regeneración del cromóforo utilizado.

Planktonic ciliates Choreotrichida and Strombidiida from the inner zone of Bahía Blanca Estuary, Argentina

Seven species of aloricate planktonic ciliates were identified using protargol staining. Choreotrichida: Strombidinopsidae, Strombidinopsis elongata Song & Bradbury, 1998; Strobiliidae, Strobilidium epacrum Lynn & Montagnes, 1988 and Strombidiida: Strombidiidae, Strombidium capitatum (Leegaard, 1915) Kahl, 1932; S. emergens (Leegaard, 1915) Kahl, 1932; S. acutum Leegaard, 1915; S. dalum Lynn, Montagnes & Small, 1988 and Cyrtostrombidium longisomum Lynn & Gilron, 1993; they were collected from the inner zone of the Bahía Blanca estuary in the southern region of the Buenos Aires province, Argentina. These species represent new records to South America (Argentina).

The Evolution of roommate networks: a comment on Jackson and Watts JET (2002)

We extend Jackson and Watts's (2002) result on the coincidence of S-stochastically stable and core stable networks from marriage problems to roommate problems. In particular, we show that the existence of a side-optimal core stable network, on which the proof of Jackson and Watts (2002) hinges, is not crucial for their result.

Albuterol delivery in an in vitro pediatric ventilator lung model: comparison of jet, ultrasonic, and mesh nebulizers.

OBJECTIVE: : To determine the influence of nebulizer types and nebulization modes on bronchodilator delivery in a mechanically ventilated pediatric lung model. DESIGN: : In vitro, laboratory study. SETTING: : Research laboratory of a university hospital. INTERVENTIONS: : Using albuterol as a marker, three nebulizer types (jet nebulizer, ultrasonic nebulizer, and vibrating-mesh nebulizer) were tested in three nebulization modes in a nonhumidified bench model mimicking the ventilatory pattern of a 10-kg infant. The amounts of albuterol deposited on the inspiratory filters (inhaled drug) at the end of the endotracheal tube, on the expiratory filters, and remaining in the nebulizers or in the ventilator circuit were determined. Particle size distribution of the nebulizers was also measured. MEASUREMENTS AND MAIN RESULTS: : The inhaled drug was 2.8% ± 0.5% for the jet nebulizer, 10.5% ± 2.3% for the ultrasonic nebulizer, and 5.4% ± 2.7% for the vibrating-mesh nebulizer in intermittent nebulization during the inspiratory phase (p < 0.01). The most efficient nebulizer was the vibrating-mesh nebulizer in continuous nebulization (13.3% ± 4.6%, p < 0.01). Depending on the nebulizers, a variable but important part of albuterol was observed as remaining in the nebulizers (jet and ultrasonic nebulizers), or being expired or lost in the ventilator circuit (all nebulizers). Only small particles (range 2.39-2.70 µm) reached the end of the endotracheal tube. CONCLUSIONS: : Important differences between nebulizer types and nebulization modes were seen for albuterol deposition at the end of the endotracheal tube in an in vitro pediatric ventilator-lung model. New aerosol devices, such as ultrasonic and vibrating-mesh nebulizers, were more efficient than the jet nebulizer.

The endodermis--development and differentiation of the plant's inner skin.

Controlling external compound entrance is essential for plant survival. To set up an efficient and selective sorting of nutrients, free diffusion via the apoplast in vascular plants is blocked at the level of the endodermis. Although we have learned a lot about endodermal specification in the last years, information regarding its differentiation is still very limited. A differentiated endodermal cell can be defined by the presence of the "Casparian strip" (CS), a cell wall modification described first by Robert Caspary in 1865. While the anatomical description of CS in many vascular plants has been very detailed, we still lack molecular information about the establishment of the Casparian strips and their actual function in roots. The recent isolation of a novel protein family, the CASPs, that localizes precisely to a domain of the plasma membrane underneath the CS represents an excellent point of entry to explore CS function and formation. In addition, it has been shown that the endodermis contains transporters that are localized to either the central (stele-facing) or peripheral (soil-facing) plasma membranes. These features suggest that the endodermis functions as a polar plant epithelium.

Permian-polysulphide-siderite-barite-haematite deposit Rude in Samoborska Gora Mts., Zagorje-Mid-Transdanubian zone of the Inner Dinarides

Samoborska Gora Mts. is situated within the westernmost part of the Zagorje-Mid-Transdanubian zone of the Internal Dinarides. The Samoborska Gora Mts. predominantly consists of Permian unmetamorphosed siliciclastic sediments and evaporites, overlain by Lower Triassic sediments. Rude mineralisation is hosted by Permian siliciclastic sediments, below gypsum and anhydrite strata. The central part of the deposit consists of a 1.5 km long stratabound mineralisation, grading laterally into ferruginous sandstone and protruding vertically into a gypsum-anhydrite layer. Siderite-polysulphide-barite-quartz veins are located below the stratabound mineralisation. The stratiform part of the deposit is situated above the stratabound and consists of haematite layer with barite concretions and veinlets. Late stage galena-barite veins overprint earlier types of mineralisation. The Rude ore deposit was generated by predominantly NaCl +/- CaCl(2)-H(2)O solutions. Detrital quartz from stratiform mineralisation contains fluid inclusions with salinities between 7 and 11 wt. % NaCl equ., homogenizing between 150 degrees C to 230 degrees C. Stratabound/siderite-polysulphide-barite-quartz vein type mineralisation was derived from solutions with salinities between 5 and 19 wt. % NaCl equ., homogenizing between 60 degrees C and 160 degrees C, while late stage galenabarite veins were precipitated from solutions with salinities between 11 and 16 wt. % NaCl equ., homogenizing between 100 degrees C to 140 degrees C. Fluid inclusion bulk leachate chemistry recorded Na(+)> Mg(2+)>K(+)>Ca(2+)>Li(+) and Cl-> SO(4)(2-) ions. Sulphur isotope composition of barites and overlying gypsum stems from Permian seawater sulphate, supported by increased Br(-) content, which follows successively the seawater evaporation line. The sulphur isotopic composition of sulphides varies between -0.2 and + 12.5 parts per thousand , as a result of thermal reduction of Permian marine sulphate. Ore-forming fluids were produced by hydrothermal convective cells (reflux brine model), and were derived primarily from Permian seawater, modified by evaporation and interaction with Permian sedimentary rocks. Rude deposits in Samoborska Gora Mts. may be declared as a prototype of the Permian siderite-polysulphide-barite deposits (products of rifting along the passive Gondwana margin), in the Inner Dinarides, and their equivalents extending northeastward into the Zagorje-Mid-Transdanubian Zone and the Gemerides, and southeastward to the Hellenide-Albanides.

Resurgence of inner solutions for perturbations of the McMillan map

A sequence of “inner equations” attached to certain perturbations of the McMillan map was considered in [MSS09], their solutions were used in that article to measure an exponentially small separatrix splitting. We prove here all the results relative to these equations which are necessary to complete the proof of the main result of [MSS09]. The present work relies on ideas from resurgence theory: we describe the formal solutions, study the analyticity of their Borel transforms and use ´Ecalle’s alien derivations to measure the discrepancy between different Borel-Laplace sums.