We construct a general measure for the degree of non-Markovian behavior in open quantum systems. This measure is based on the trace distance which quantifies the distinguishability of quantum states. ...It represents a functional of the dynamical map describing the time evolution of physical states, and can be interpreted in terms of the information flow between the open system and its environment. The measure takes on nonzero values whenever there is a flow of information from the environment back to the open system, which is the key feature of non-Markovian dynamics.
A
bstract
Many lattice studies of heavy quark diffusion originate from a colour-electric correlator, obtained as a leading term after an expansion in the inverse of the heavy-quark mass. In view of ...the fact that the charm quark is not particularly heavy, we consider subleading terms in the expansion. Working out correlators up to
O
(1
/M
2
), we argue that the leading corrections are suppressed by
O
(T/M
), and one of them can be extracted from a colour-magnetic correlator. The corresponding transport coefficient is non-perturbative already at leading order in the weak-coupling expansion, and therefore requires a nonperturbative determination.
This article contributes to the research agenda of emancipatory entrepreneurship by developing the understanding of emancipation as a social imaginary in entrepreneurship. In particular, we draw on ...fiction and philosophical hermeneutics to generate three ideal types of the social imaginary of emancipation in entrepreneurship theorizing. Building on our hermeneutic analysis, we introduce a framework that explains how entrepreneurship theorizing can strengthen, undermine, and shape emancipatory practices as well as the social imaginary of emancipation. We conclude our article by explicating and discussing the relevancy of emancipation in and for entrepreneurship theorizing across different social imaginaries and social practices.
Abstract
Context:
Osteocytes express proteins that regulate bone remodeling and mineralization.
Objective:
To evaluate the relationship between osteocyte-specific protein expression and bone ...histology in patients with monogenic osteoporosis due to wingless integration site 1 (WNT1) or plastin 3 (PLS3) mutations.
Design and Setting:
Cross-sectional cohort study at a university hospital.
Participants:
Six patients (four males; ages: 14 to 72 years) with a heterozygous WNT1 mutation and five patients (four males; ages: 9 to 70 years) with a heterozygous/hemizygous PLS3 mutation.
Methods and Main Outcome Measures:
Immunohistochemistry was performed for fibroblast growth factor 23 (FGF23), dentin matrix protein 1 (DMP1), sclerostin, and phosphorylated (phospho–)β-catenin in iliac crest samples and compared with bone histomorphometry.
Results:
FGF23 expression in WNT1 patients was 243% that observed in PLS3 patients (P < 0.01). DMP1, sclerostin, and phospho–β-catenin expression did not differ between groups. Serum phosphate correlated inversely with FGF23 expression (r = −0.79, P = 0.01) and serum ionized calcium correlated inversely with sclerostin expression (r = −0.60, P = 0.05). Phospho–β-catenin expression correlated inversely with DMP1 expression (r = −0.88, P < 0.001), osteoid volume/bone volume (r = −0.68, P = 0.02), and bone formation rate (r = −0.78, P < 0.01). FGF23 expression did not correlate with DMP1 expression, sclerostin expression, or bone histomorphometry. Marrow adiposity was higher in WNT1 than in PLS3 patients (P = 0.04).
Conclusions:
Mutations that disrupt WNT signaling and osteocytic mechanosensing affect osteocyte protein expression. Abnormal osteocyte function may play a role in the pathogenesis of monogenetic forms of osteoporosis.
We studied bone from six WNT1 and five PLS patients. Bone FGF23 was higher in WNT1 than in PLS3 patients. Phospho–β-catenin correlated inversely with DMP1 and with bone turnover.
It has been argued by Caron-Huot that infrared contributions to the jet quenching parameter in hot QCD, denoted by
, can be extracted from an analysis of a certain static-potential related ...observable within the dimensionally reduced effective field theory. Following this philosophy, the order of magnitude of a non-perturbative contribution to
from the colour-magnetic scale,
g
2
T
/
π
, is estimated. The result is small; it is probably below the parametrically perturbative but in practice slowly convergent contributions from the colour-electric scale, whose all-orders resummation therefore remains an important challenge.
A
bstract
Heavy quarks placed within a hot QCD medium undergo Brownian motion, characterized by specific transport coefficients. Their determination can be simplified by expanding them in
T/M
, where
...T
is the temperature and
M
is a heavy quark mass. The leading term in the expansion originates from the colour-electric part of a Lorentz force, whereas the next-to-leading order involves the colour-magnetic part. We measure a colour-magnetic 2-point correlator in quenched QCD at
T
∼ (1
.
2
−
2
.
0)
T
c
. Employing multilevel techniques and non-perturbative renormalization, a good signal is obtained, and its continuum extrapolation can be estimated. Modelling the shape of the corresponding spectral function, we subsequently extract the momentum diffusion coefficient,
κ
. For charm (bottom) quarks, the magnetic contribution adds ∼ 30% (10%) to the electric one. The same increases apply also to the drag coefficient,
η
. As an aside, the colour-magnetic spectral function is computed at NLO.
This study offers an updated bioeconomy perspective on biobased routes to high-purity silicon and silica in the context of the societal, economic and environmental trends reshaping chemical ...processes. We summarize the main aspects of the green chemistry technologies capable of transforming current production methods. Coincidentally, we discuss selected industrial and economic aspects. Finally, we offer perspectives of how said technologies could/will reshape current chemical and energy production.
Polymer-based solid electrolytes containing ceramic nanoparticles are attractive alternatives to liquid electrolytes for high-energy density Li batteries. In this study, three different types of ...fillers have been dispersed in poly(ethylene) oxide (PEO) polymer matrices, and the effects on the resulting ionic conductivity of the nanocomposites have been examined. In this respect, the efficacy of one active, liquid-feed flame spray pyrolysis synthesized amorphous Li1.3Al0.3Ti1.7(PO4)3 (LATP), and two passive filler materials, TiO2 and fumed silica nanoparticles, are compared. Nanocomposite electrolytes are prepared with up to 20 wt % particle loadings. PEO/LiClO4 with 10 wt % LATP nanoparticles exhibits an ionic conductivity of 1.70 × 10–4 S·cm–1 at 20 °C, the highest among the surveyed systems, despite exhibiting comparable or higher degrees of crystallinity and glass transition temperatures than the systems containing passive fillers. The ionic conductivity of the composites with LATP nanoparticles exceed that of the polymer matrix by 1 to 2 orders of magnitude. We attribute this remarkable enhancement to cation transport within the interphase region surrounding the particles, which achieves percolation at low nanoparticle loading. The development of this interphase structure is influenced by the active nature of the LATP filler, and we estimate the inherent conductivity of the interphase to be 3 to 4 times higher than the maximum measured value.
•Global response to environmental crisis lacks sufficient urgency.•Calls for rethinking of timeframes used in conventional and environmental accounting.•Current long-term environmental accounting ...contributes to a lack of urgent response.•Short-term environmental accounting needed to supplement sustainability accounting.•Short-term environmental accounting needed to emphasise urgency and respond to crisis.
The environment is in crisis. Climate science and biodiversity loss indicators, for example, illustrate the extent of environmental degradation and the concerns with the sustainability of Earth, or perhaps more specifically, the ability of Earth to sustain (human) life. There is also an increasing recognition of the environmental crisis as urgent, as an emergency, yet whether we are acting sufficiently to the environmental crisis is still up for debate. These debates have become more evident in light of the COVID-19 pandemic, creating a context within which to consider what it means to respond to a crisis and how the environment might feature in any post-COVID recovery. In this essay, we first outline and reflect on crisis, urgency and (in)action through a consideration of the environmental crisis and the COVID-19 crisis before moving to our main focus – the implications for environmental accounting. Specifically, we suggest that the construction of environmental accounting as accounting for the long-term, an attempt to contrast it with and overcome the problems with short-term conventional accounting, potentially contributes to the construction of the environment as lacking urgency and potentially enables its marginalisation. We argue that in order to make the most of accounting’s potential as a constitutive force, capable of participating in transforming preferences, decisions and behaviour in organisations and societies, environmental accounting needs to be about the short-term. We contribute to the ongoing discussions on how accounting needs to change if it is to recognise the urgent nature of the environmental crisis.
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