A de Finetti representation for finite symmetric quantum states

Consider a symmetric quantum state on an n-fold product space, that is, the state is invariant under permutations of the n subsystems. We show that, conditioned on the outcomes of an informationally complete measurement applied to a number of subsystems, the state in the remaining subsystems is close to having product form. This immediately generalizes the so-called de Finetti representation to the case of finite symmetric quantum states.Comment: 22 pages, LaTe

IEA annex 58 : full-scale empirical validation of detailed thermal simulation programs

As simulation programs become more widely used for building performance assessment and building regulations compliance, there is a need to ensure that there are good quality empirical datasets which can be used to assess the predictive accuracy of these programs. This paper summarises a detailed experiment carried out on two identical full-scale buildings located at the Fraunhofer IBP test site at Holzkirchen in Germany and the associated modelling of the buildings. The work was undertaken as part of IEA ECB Annex 58 "Reliable building energy performance characterization based on full scale dynamic measurements". The test sequence, applied to the side-by-side validation experiment conducted on the multi-roomed Twin Houses, consisted of periods of constant internal temperatures, a period of pseudo-random heat injections and a free-float period. All boundary and internal conditions were comprehensively monitored. Modelling teams were given details of the buildings and the boundary conditions, and over 20 teams submitted their predictions of the internal conditions which were subsequently compared with measurements. The paper focuses on a sensitivity study carried out to assess the overall prediction uncertainty resulting from the uncertainties in the input parameters, as well as identifying those inputs which had the most influence on predictions. An assessment of the measurement uncertainty is also included

Weighing the Galactic disk using phase-space spirals III. Probing distant regions of the disk using the Gaia EDR3 proper motion sample

We have applied our method for weighing the Galactic disk using phase-space spirals to the Gaia EDR3 proper motion sample. For stars in distant regions of the Galactic disk, the latitudinal proper motion has a close projection with vertical velocity, such that the phase-space spiral in the plane of vertical position and vertical velocity can be observed without requiring that all stars have available radial velocity information. We divided the Galactic plane into 360 separate data samples, each corresponding to an area cell in the Galactic plane in the distance range of 1.4-3.4 kpc, with an approximate cell length of 200-400 pc. Roughly half of our data samples were disqualified altogether due to severe selection effects, especially in the direction of the Galactic centre. In the remainder, we were able to infer the vertical gravitational potential by fitting an analytic model of the phase-space spiral to the data. This work is the first of its kind, in the sense that we are weighing distant regions of the Galactic disk with a high spatial resolution, without relying on the strong assumptions of axisymmetry. Post-inference, we fit a thin disk scale length of $2.2\pm 0.1$ kpc, although this value is sensitive to the considered spatial region. We see surface density variations as a function of azimuth on the order of 10-20 %, which is roughly the size of our estimated sum of potential systematic biases. With this work, we have demonstrated that our method can be used to weigh distant regions of the Galactic disk despite strong selection effects. We expect to reach even greater distances and improve our accuracy with future Gaia data releases and further improvements to our method.Comment: 18 pages, 19 figures, accepted for publication in A&

Sequence randomness and polymer collapse transitions

Contrary to expectations based on Harris' criterion, chain disorder with frustration can modify the universality class of scaling at the theta transition of heteropolymers. This is shown for a model with random two-body potentials in 2D on the basis of exact enumeration and accurate Monte Carlo results. When frustration grows beyond a certain finite threshold, the temperature below which disorder becomes relevant coincides with the theta one and scaling exponents definitely start deviating from those valid for homopolymers.Comment: 4 pages, 4 eps figure

Reinvestigation of the tautomerism of some substituted 2-hydroxypyridines

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Adverse Perinatal Outcome in Subsequent Pregnancy after Stillbirth by Placental Vascular Disorders

Objective: To evaluate outcome in the pregnancy following a stillbirth (SB) by a placental vascular disorders. Study Design: A prospective, observational, multicenter study was conducted in woman with a history of stillbirth (> 22 weeks) between 2005 and June 2013, in 3 Italian University Hospitals. Causes of SB were previously identified after extensive investigations. Pregnant women were enrolled within the first trimester. The main outcome was "adverse neonatal outcome", including perinatal death, fetal growth restriction, early preterm birth <33+6 weeks, hypoxicischemic encephalopathy, intracranial hemorrhage or respiratory distress. Results: Out of 364 index pregnancies, 320 women (87.9%) had a subsequent pregnancy during the study period. Forty-seven had an early pregnancy loss. Out of 273 babies, 67 (24.5%) had an adverse perinatal outcome, including 1 SB and 1 early neonatal death (3.7/1000). Women who had a SB related to placental vascular disorders (39.6%), were at higher risk of an adverse neonatal outcome compared with women whose SB was unexplained or resulted from other causes (Adj. OR = 2.1, 95%CI: 1.2-3.8). Moreover, also obesity independently predicts an adverse perinatal outcome (Adj OR = 2.1, 95%CI: 1.1-4.3). Conclusion: When previous SB is related to placental vascular disorders there is a high risk for adverse neonatal outcomes in the subsequent pregnancy. Maternal obesity is an additional risk factor

Virological and Immunological Monitoring of Human Cytomegalovirus Infection in Heart and Small Bowel/Multivisceral Transplantation

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