Minkowski space structure of the Higgs potential in 2HDM: II. Minima, symmetries, and topology

We continue to explore the consequences of the recently discovered Minkowski space structure of the Higgs potential in the two-Higgs-doublet model. Here, we focus on the vacuum properties. The search for extrema of the Higgs potential is reformulated in terms of 3-quadrics in the 3+1-dimensional Minkowski space. We prove that 2HDM cannot have more than two local minima in the orbit space and that a twice-degenerate minimum can arise only via spontaneous violation of a discrete symmetry of the Higgs potential. Investigating topology of the 3-quadrics, we give concise criteria for existence of non-contractible paths in the Higgs orbit space. We also study explicit symmetries of the Higgs potential/lagrangian and their spontaneous violation from a wider perspective than usual.Comment: 27 pages, 5 figure

The WFCAM Multi-wavelength Variable Star Catalog

Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for the time-domain exploration of the NIR sky. We perform a comprehensive search for stellar variability using the optical-NIR multi-band photometric data in the public Calibration Database of the WFCAM Science Archive (WSA), with the aim of contributing to the general census of variable stars, and to extend the current scarce inventory of accurate NIR light curves for a number of variable star classes. We introduce new variability indices designed for multi-band data with correlated sampling, and apply them for pre-selecting variable star candidates, i.e., light curves that are dominated by correlated variations, from noise-dominated ones. Pre-selection criteria are established by robust numerical tests for evaluating the response of variability indices to colored noise characteristic to the data. We find 275 periodic variable stars and an additional 44 objects with suspected variability with uncertain periods or apparently aperiodic variation. Only 44 of these objects had been previously known, including 11 RR~Lyrae stars in the outskirts of the globular cluster M3 (NGC~5272). We provide a preliminary classification of the new variable stars that have well-measured light curves, but the variability types of a large number of objects remain ambiguous. We classify most of the new variables as contact binary stars, but we also find several pulsating stars, among which 34 are probably new field RR~Lyrae and 3 are likely Cepheids. We also identify 32 highly reddened variable objects close to previously known dark nebulae, suggesting that these are embedded young stellar objects. We publish our results and all light-curve data as the WFCAM Variable Star Catalog.Comment: 21 pages, 11 figure

Morphology and physiology of anaerobic granular sludge exposed to organic solvents

The use of quantitative image analysis techniques, together with physiological information might be used to monitor and detect operational problems in advance to reactor performance failure. Industrial organic solvents such as white spirit are potentially harmful to granular sludge. In preliminary batch assays, 33 mg.Lˉ¹ of solvent caused 50% relative biomass activity loss. In an Expanded Granular Sludge Blanket reactor fed with 40 mg.Lˉ¹ of solvent, during 222 h, the reactor performance seemed to be unaffected, presenting COD removal efficiency constantly above 95 %. However, in the first hours of exposure the specific acetoclastic and the specific hydrogenotrophic methanogenic activities decreased by 29 and 21 %, respectively. The % of projected aggregates area with equivalent diameter (Deq) higher than 1 mm decreased from 81 to 53 % and consequently the % of projected area of small aggregates increased. The average equivalent diameter of the aggregates larger than 2 mm decreased as well as the settling velocity, showed that the granules experienced fragmentation phenomenon caused by the solvent shock load. The ratio between total filaments length and total aggregates projected area (LfA) increased 2 days before effluent volatile suspended solids, suggesting that LfA could be an early-warning indicator of washout events.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/13317/2003, POCTI/AMB/60141/2001

To be or not to be digital, that's the question! Implications for firm innovation capability and performance

Digital transformation emerges today as a process for attaining competitive advantages and company differentiation. However, what are the implications of these digital processes for the innovative capability and performance of companies? This study seeks to contribute towards a better understanding of this framework, analysing the factors that lead companies to adopt new digital processes and their consequences in terms of innovation capability and performance. Using a sample of 940 companies and recourse to multivariate statistical analysis, we conclude that the profile of the owner/manager and the adoption of new digital processes reflect in the greater competitiveness of these (digital) companies.info:eu-repo/semantics/acceptedVersio

Tenure matters for team cohesion and performance: The moderating role of trust in the coach

Research question: This study examines team performance as a function of team tenure, cohesion and trust in the coach. Specifically, we propose a moderated-mediation model to explain whether it translates into an objective measure of future team performance. Research methods: The study sample consists of 668 players from 73 professional and top amateur basketball league teams in Catalonia, Spain. Data collection consisted of a survey performed during a regular training session held at the beginning of the second part of the season as well as objective and subjective team performance indicators. Results and findings: Our findings suggest that the indirect effect of team tenure on performance through team cohesion is only significant for high and medium levels of cognitive trust in the coach and low levels of affective trust in the coach. Implications: These findings provide evidence that explains trust’s contribution to fostering team dynamics and how team tenure translates into future team performance. The practical implications of this study suggest that simply promoting team cohesion without taking into account the cognitive trust in the coach will not necessarily increase performance. Therefore, coaches and managers must invest in the amount of work they do with team members and their skills in order to ensure team members have high cognitive trust in them.info:eu-repo/semantics/acceptedVersio

Transformational leadership and team performance in sports teams: A conditional indirect model

This study tests how transformational leadership fosters team performance through team cohesion and how that relationship is moderated by previous team performance and leadership consensus. We computed a moderated-mediation model based on a sample of 690 professional players in 59 top professional teams in interactive team sports leagues (basketball, handball, roller hockey, and indoor football/soccer) in Spain. Our findings suggest that transformational leadership indirectly influences objective team performance through the mediation role of team cohesion and that this indirect effect is more prominent when the level of previous performance is higher. We also found that the indirect effect of transformational leadership on team performance via cohesion is stronger in teams with higher consensus regarding their coaches' leadership. Overall, our results demonstrate the importance of integrating dispersion and contextual variables into research models, in particular, previous performance and leadership consensus.info:eu-repo/semantics/publishedVersio

Lorentz-violating contributions of the Carroll-Field-Jackiw model to the CMB anisotropy

We study the finite temperature properties of the Maxwell-Carroll-Field-Jackiw (MCFJ) electrodynamics for a purely spacelike background. Starting from the associated finite temperature partition function, a modified black body spectral distribution is obtained. We thus show that, if the CMB radiation is described by this model, the spectrum presents an anisotropic angular energy density distribution. We show, at leading order, that the Lorentz-breaking contributions for the Planck's radiation law and for the Stefan-Boltzmann's law are nonlinear in frequency and quadratic in temperature, respectively. Using our results, we set up bounds for the Lorentz-breaking parameter, and show that Lorentz violation in the context of the MCFJ model is unable to yield the known CMB anisotropy (of 1 part in $10^{5})$

Coriolis Effect on Dynamic Stall in a Vertical Axis Wind Turbine at Moderate Reynolds Number

The immersed boundary method is used to simulate the flow around a two-dimensional rotating NACA 0018 airfoil at sub-scale Reynolds number in order to investigate the separated flow occurring on a vertical-axis wind turbine. The influence of dynamic stall on the forces is characterized as a function of tip-speed ratio. The influence of the Coriolis effect is also investigated by comparing the rotating airfoil to one undergoing a equivalent planar motion, which is composed of surging and pitching motions that produce an equivalent speed and angle-of-attack variation over the cycle. When the angle of attack of a rotating airfoil starts to decrease in the upwind half cycle, the Coriolis force leads to a wake-capturing phenomenon of a vortex pair at low tip-speed ratio. This effects occurs at a slightly different phase in each cycle and leads to a significant decrease in the average lift during the downstroke phase. Moreover, the wake-capturing is only observed when the combination of surging, pitching, and Coriolis force are present. Finally, an actuator model is placed at an appropriate location on the suction side of the airfoil surface to control the wake-capturing phenomenon. Based on preliminary simulations, a momentum coefficient above 0.02 was able to increase the average lift by more than 70% over the upwind-half cycle

Respostas morfofisiológica da dinâmica foliar de curauá (Ananas erectifolius L.B. Sm.) ao regime hídrico, sob cultivo em sistemas agroflorestais.

Dada as diferentes funções que a água sobre as exerce plantas e as diferentes condições aonde a planta vem sendo cultivada, o trabalho teve como objetivo avaliar respostas morfofisiológica da dinâmica foliar de curauá ao regime hídrico, sob cultivo em sistemas agroflorestais

12-Year-Old Female with Mucocutaneous Lesions

info:eu-repo/semantics/publishedVersio