Time-resolved photometry of the nova remnants DM Gem, CP Lac, GI Mon, V400 Per, CT Ser and XX Tau

We present the first results of a photometric survey of poorly studied nova remnants in the Northern Hemisphere. The main results are as follows: DM Gem shows a modulation at 0.123 d (probably linked to the orbit) and rapid variations at ∼22 min. A moderate resolution spectrum taken at the time of the photometric observations shows intense He II λ4686 and Bowen emission, characteristic of an intermediate polar or a SW Sex star. Variability at 0.127 d and intense flickering (or quasi-periodic oscillations) are the main features of the light curve of CP Lac. A 0.1-mag dip lasting for ∼45 min is observed in GI Mon, which could be an eclipse. A clear modulation (probably related to the orbital motion) either at 0.179 d or 0.152 d is observed in the B-band light curve of V400 Per. The results for CT Ser point to an orbital period close to 0.16 d. Intense flickering is also characteristic of this old nova. Finally, XX Tau shows a possible periodic signal near 0.14 d and displays fast variability at ∼24 min. Its brightness seems to be modulated at ∼5 d. We relate this long periodicity to the motion of an eccentric/tilted accretion disc in the binary

Communicating Resilience: A Discursive Leadership Perspective

In this essay we challenge whether current conceptions of optimism, hope, and resilience are complete enough to account for the complexity and nuance of developing and maintaining these in practice. For example, a quick perusal of popular outlets (e.g., Forbes, Harvard Business Review) reveals advice to managers urging them to “be optimistic,” or “be happy” so that these types of emotions or feelings can spread to the workplace. One even finds simple advice and steps to follow on how to foster these types of things in the workplace (McKee; Tjan). We argue that this common perspective focuses narrowly on individuals and does not account for the complexity of resilience. Consequently, it denies the role of context, culture, and interactions as ways people develop shared meaning and reality. To fill this gap in our understanding, we take a social constructionist perspective to understand resilience. In other words, we foreground communication as the primary building block to sharing meaning and creating our worlds. In so doing, we veer away from the traditional focus on the individual and instead emphasise the social and cultural elements that shape how meaning is shared by peoples in various contexts (Fairhurst, Considering Context). Drawing on a communication, discourse-centered perspective we explore hope and optimism as concepts commonly associated with resilience in a work context. At work, leaders play a vital role in communicating ways that foster resilience in the face of organisational issues and events (e.g., environmental crises, downsizing). Following this lead, discursive leadership offers a framework that positions leadership as co-created and as the management of meaning through framing (Fairhurst, Power of Framing). Thus, we propose that a discursive leadership orientation can contribute to the communicative construction of resilience that moves away from individual perspectives to an emphasis on the social. From a discursive perspective, leadership is defined as a process of meaning management; attribution given by followers or observers; process-focused rather than leader-focused; and as shifting and distributed among several organizational members (Fairhurst Power of Framing). By switching from the individual focus and concentrating on social and cultural systems, discursive leadership is able to study concepts related to subjectivity, cultures, and identities as it relates to meaning. Our aim is to offer leaders an alternative perspective on resilience at the individual and group level by explaining how a discursive orientation to leadership can contribute to the communicative construction of resilience. We argue that a social constructionist approach provides a perspective that can unravel the multiple layers that make up hope, optimism, and resilience. We begin with a peek into the social scientific perspective that is so commonplace in media and popular portrayals of these constructs. Then, we explain the social constructionist perspective that grounds our framework, drawing on discursive leadership. Next, we present an alternative model of resilience, one that takes resilience as communicatively constructed and socially created. We believe this more robust perspective can help individuals, groups, and cultures be more resilient in the face of challenges

Quark matter equation of state and stellar properties

In this paper we study strange matter by investigating the stability window within the QMDD model at zero temperature and check that it can explain the very massive pulsar recently detected. We compare our results with the ones obtained from the MIT bag model and see that the QMDD model can explain larger masses, due to the stiffening of the equation of state

Weak value amplification: a view from quantum estimation theory that highlights what it is and what isn't

Weak value amplification (WVA) is a concept that has been extensively used in a myriad of applications with the aim of rendering measurable tiny changes of a variable of interest. In spite of this, there is still an on-going debate about its true nature and whether is really needed for achieving high sensitivity. Here we aim at solving the puzzle, using some basic concepts from quantum estimation theory, highlighting what the use of the WVA concept can offer and what it can not. While WVA cannot be used to go beyond some fundamental sensitivity limits that arise from considering the full nature of the quantum states, WVA can notwithstanding enhance the sensitivity of real detection schemes that are limited by many other things apart from the quantum nature of the states involved, i.e. technical noise. Importantly, it can do that in a straightforward and easily accessible manner.Comment: 2 pages, 5 figure