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The present study has the aim to evaluate the link between PTSD and Bipolar Disorder/Schizoaffective Disorder. There are great apparent differences between Bipolar Disorder and Schizoaffective Disorder, also many similitudes.
The sample consists of 22 patients, 14 females and 8 males, with average age 29,3 years. They were hospitalized for depressive or manic episode and diagnosed using DSM IV criteria with BPD (n1=12 patients) and Schizoaffective Disorder (n2=10). All the patients were screened for PTSD using module from the Structural Clinical Interview for DSM IV (SCID).
The study replicated the impact of PTSD on the onset of the two major disorders. In this sample, 8 from 10 patients with Schizoaffective Disorder (80%) have had PTSD (frequently after a suicide in patient`s family or rape), 3-4 years before onset. The most patients with Bipolar Disorder (n=7; 58,33%) had also a PTSD but the temporal link between this one and BD is longer (6,5 years average).
It may be concluded that PTSD is highly prevalent in patients with Schizoaffective Disorder, but there is also a great risk of having PTSD in patients with BD.
The reported incidence of Clostridoides difficile infection (CDI) has increased in recent years, partly due to broadening adoption of nucleic acid amplification tests (NAATs) replacing enzyme immunoassay (EIA) methods. Our aim was to quantify the impact of this switch on reported CDI rates using a large, multihospital, empirical dataset.
We analyzed 9 years of retrospective CDI data (2009–2017) from 47 hospitals in the southeastern United States; 37 hospitals switched to NAAT during this period, including 24 with sufficient pre- and post-switch data for statistical analyses. Poisson regression was used to quantify the NAAT-over-EIA incidence rate ratio (IRR) at hospital and network levels while controlling for longitudinal trends, the proportion of intensive care unit patient days, changes in surveillance methodology, and previously detected infection cluster periods. We additionally used change-point detection methods to identify shifts in the mean and/or slope of hospital-level CDI rates, and we compared results to recorded switch dates.
For hospitals that transitioned to NAAT, average unadjusted CDI rates increased substantially after the test switch from 10.9 to 23.9 per 10,000 patient days. Individual hospital IRRs ranged from 0.75 to 5.47, with a network-wide IRR of 1.75 (95% confidence interval, 1.62–1.89). Reported CDI rates significantly changed 1.6 months on average after switching to NAAT testing (standard deviation, 1.9 months).
Hospitals that switched from EIA to NAAT testing experienced an average postswitch increase of 75% in reported CDI rates after adjusting for other factors, and this increase was often gradual or delayed.
We present a comparative study on a 700-yr sequence of dendrochronologically ordered tree-rings of Pinus cembra originating from Eastern Carpathians for the period AD 1009–1709. This period covers the solar minima of the Little Ice Age. The aim of this study was to assess the accuracy of our radiocarbon (14C) determinations interpreted on the IntCal13 calibration data and to observe any apparent offsets. The 14C measurements on single and double tree-rings were “wiggle-matched” to secure the dendrochronology cross-matching of all the Pinus cembra wood pieces. The results showed a very good agreement between the age datasets for four out of five wood trunks. However, for one of them a new cross-matching was performed after a quality assurance test, establishing an earlier 48-yr position, recommended by wiggle-matching Bayesian statistics and dendrochronological analysis. Following this adjustment, the quantification of the 14C level variability with respect to the IntCal13 calibration curve was obtained by calculating Δ14C for all tree-ring samples. As a final conclusion, an insignificant 14C concentration offset of –0.63 ± 3.76‰ was found for the Romanian samples.
The aim of this work is to explore the connection between variability in single pulse intensity and periodic switching of the position angle (PA) of the linear polarisation and how this relates to the radio emission mechanism. There are five pulsars reported in the literature for which the PA is seen to periodically change in tandem with the variability in their pulse shapes. This behaviour is seemingly incompatible with two well established models of the radio emission mechanism. The purpose of this study is to investigate in a systematic way whether this phenomenon is common or if only happens in special cases, using a high-quality sample of pulsar data observed with the Parkes telescope. We show that the connection between polarisation variability and intensity variability is more common than previously expected.
We consider two players, starting with m and n units, respectively. In each round, the winner is decided with probability proportional to each player's fortune, and the opponent loses one unit. We prove an explicit formula for the probability p(m, n) that the first player wins. When m ~ Nx0, n ~ Ny0, we prove the fluid limit as N → ∞. When x0 = y0, z → p(N, N + z√N) converges to the standard normal cumulative distribution function and the difference in fortunes scales diffusively. The exact limit of the time of ruin τN is established as (T - τN) ~ N-βW1/β, β = ¼, T = x0 + y0. Modulo a constant, W ~ χ21(z02 / T2).
We consider a game with K ≥ 2 players, each having an integer-valued fortune. On each round, a pair (i,j) among the players with nonzero fortunes is chosen to play and the winner is decided by flipping a fair coin (independently of the process up to that time). The winner then receives a unit from the loser. All other players' fortunes remain the same. (Once a player's fortune reaches 0, this player is out of the game.) The game continues until only one player wins all. The choices of pairs represent the control present in the problem. While it is known that the expected time to ruin (i.e. expected duration of the game) is independent of the choices of pairs (i,j) (the strategies), our objective is to find a strategy which maximizes the variance of the time to ruin. We show that the maximum variance is uniquely attained by the (optimal) strategy, which always selects a pair of players who have currently the largest fortunes. An explicit formula for the maximum value function is derived. By constructing a simple martingale, we also provide a short proof of a result of Ross (2009) that the expected time to ruin is independent of the strategies. A brief discussion of the (open) problem of minimizing the variance of the time to ruin is given.
Irregular immigration in Europe comes in many shapes and forms. It includes, for example, an international student who did not apply for an extension of his or her residence permit, an Australian backpacker working a temporary job to earn some money before travelling on, and an Eastern European domestic servant in a neighbour's home. Irregular migrants are a mostly invisible group in our society, and it is safe to say that each European country has its share. Beyond the national implications, there is a pan-European dimension to irregular immigration due to the process of European integration, which has rendered European Union member states dependent on one another. In both national and European politics, how member states and the EU respond to this phenomenon, or better yet, how they should respond, represents one of the most contentious political debates today.
Even if irregular migrants are forced by virtue of their status to lead a ‘hidden’ existence, the discussions they generate rank high and take place openly in local, national and international fora. They are never far from the public eye – though they are usually cast in extremes. Irregular immigrants may be held accountable for an array of social ills, while individual cases of tragedy and lost lives provoke compassion.
There is a growing empirical literature on irregular migrants in Europe (Alt 2003; Düvell 2006a; Van Nieuwenhuyze 2008; Van Meeteren et al. 2008; Schrover et al. 2008). Form this we learn that irregular immigrants are primarily men (though the proportion of women is increasing), between 20 and 40 years of age, and they migrate from relatively poor areas to more affluent regions. They are prepared to do jobs that natives shun, often under poor conditions, for wages that are usually lower than those acceptable to legal residents. Contrary to conventional views, most irregular immigrants do not enter the country of destination by crossing a border undocumented. More often, they enter with legal permission (a visa) and overstay, or otherwise violate the terms of their admission. Though all European countries face irregular migration, the ‘contexts of reception’ (Portes and Rumbaut 1990) and opportunity structures differ highly across time and space.
A model of heterogeneous, composite material is introduced, consisting of randomly distributed identical structural micro-domains endowed with electric charges or dipoles. Two cases are presented, one corresponding to a tightly packed (dense) material, another corresponding to highly-dispersed, small domains. The polarizability is computed in both cases, under the action of an external uniform electric field oscillating in time (a quasi-stationary field), and it is related to the displacement of the micro-domains from their positions of local equilibrium (translations or rotations). It is shown that the polarizability (or electric susceptibility) can exhibit characteristic (resonance) frequencies in the radio-frequency range and, even for moderate external fields, the material can undergo a displacive transition (similar to a ferroelectric transition), governed by non-linearities in the interaction energy of the micro-domains. The shift in the characteristic frequencies of the polarizability is estimated, as caused by the displacive modification.
The influence of angle-of-attack and vortex-aerofoil vertical miss-distance on the aerofoil-vortex mechanism of interaction is investigated numerically using the large-eddy simulation approach. The study concerns the aerofoil-vortex interaction (AVI) phenomena encountered in the rotorcraft aerodynamics. The studies are performed for a Reynolds number of 1·3 × 106 based on the chord (c = 0·2m) of the aerofoil and free-stream velocity U = 100ms−1. The studies are conducted for three different angles-of-attack (α = 0°, and α = 5°, α = 10°) and vertical miss-distances (h = 0·0m, h = −0·01, h = −0·02m) respectively. The present study shows that the magnitude of lift coefficient and flow separation, at the instant of interaction, decay with the increase of angle-of-attack and vertical miss-distance.
The task of planning a path between two spatial configurations of an artifact moving among obstacles is an important problem in practically all geometrically intensive applications. Despite the ubiquity of the problem, the existing approaches make specific limiting assumptions about the geometry and mobility of the obstacles, or those of the environment in which the motion of the artifact takes place. We present a strategy to construct a family of paths, or roadmaps, for two- and three-dimensional solids moving in an evolving environment that can undergo drastic topological changes. Our approach is based on a potent paradigm for constructing geometric skeletons that relies on constructive representations of shapes with R-functions that operate on real-valued half-spaces as logic operations. We describe a family of skeletons that have the same homotopy as that of the environment and contains the medial axis as a special case. Of importance, our skeletons can be designed so that they are “attracted to” or “repulsed by” prescribed spatial sites of the environment. Moreover, the R-function formulation suggests the new concept of a medial zone, which can be thought of as a “thick” skeleton with significant applications for motion planning and other geometric reasoning applications. Our approach can handle problems in which the environment is not fully known a priori, and intrinsically supports local and parallel skeleton computations for domains with rigid or evolving boundaries. Furthermore, our path planning algorithm can be implemented in any commercial geometric kernel, and has attractive computational properties. The capability of the proposed technique are explored through several examples designed to simulate highly dynamic environments.
We describe a general method of arithmetic coding of geodesics on the modular surface based on the study of one-dimensional Gauss-like maps associated to a two-parameter family of continued fractions introduced in [Katok and Ugarcovici. Structure of attractors for (a,b)-continued fraction transformations. J. Modern Dynamics4 (2010), 637–691]. The finite rectangular structure of the attractors of the natural extension maps and the corresponding ‘reduction theory’ play an essential role. In special cases, when an (a,b)-expansion admits a so-called ‘dual’, the coding sequences are obtained by juxtaposition of the boundary expansions of the fixed points, and the set of coding sequences is a countable sofic shift. We also prove that the natural extension maps are Bernoulli shifts and compute the density of the absolutely continuous invariant measure and the measure-theoretic entropy of the one-dimensional map.
In a general model (AIMD) of transmission control protocol (TCP)
used in internet traffic congestion management, the time dependent
data flow vector x(t) > 0 undergoes a biased random walk on
two distinct scales. The amount of data of each component xi(t)
goes up to xi(t)+a with probability 1-ζi(x) on
a unit scale or down to γxi(t), 0 < γ < 1 with
probability ζi(x) on a logarithmic scale, where ζi depends on the joint state of the system x. We
investigate the long time behavior, mean field limit, and the one
particle case. According to
c = lim inf|x|→∞ |x|ζi(x)
, the process drifts to ∞ in the
subcritical c < c+(n, γ) case and has an invariant
probability measure in the supercritical case c > c+(n, γ).
Additionally, a scaling limit is proved when ζi(x)
and a are of order N–1 and t → Nt, in the form of a
continuum model with jump rate α(x).
Rosai–Dorfman disease is a rare, idiopathic, histiocytic proliferative disorder with a distinctive microscopic appearance, which was formerly thought to be a disease process limited to lymph nodes. However, extranodal involvement has been documented in less than half of the reported patients, but rarely without associated lymphadenopathy.
We report the case of a 43-year-old Senegalese woman who presented with a polypoid, intranasal mass caused by Rosai–Dorfman disease. A diagnosis of a granulomatous process, including rhinoscleroma, was initially discussed. The correct diagnosis was made histologically by demonstrating aggregates of histiocytes with large amounts of cytoplasm, emperipolesis and protein S100 antigen expression. Despite using ancillary methods (molecular biology and electron microscopy), we failed to demonstrate any associated pathogen.
Diagnosis of Rosai–Dorfman disease can be very difficult, in particular in adults from Africa with pure, isolated, intranasal localisation, in whom clinical and radiological features may mimic other infectious or neoplastic disorders. The diagnosis is made based on the histological presence of large histiocytes with lymphophagocytosis. Moreover, immunohistochemical analysis of these histiocytes using anti-protein S100 antibody shows strong positivity.
For a locally compact group G, let B(G) denote its Fourier–Stieltjes algebra. Any continuous, piecewise affine map α: Y ⊂ H → G induces a completely bounded algebra homomorphism jα: B(G) → B(H) [14, 15] and we prove that jα is w* – w* continuous if and only if α is an open map. This extends one of the main results in , due to M.B. Bekka, E. Kaniuth, A.T. Lau and G. Schlichting. Several classical theorems regarding isomorphisms and extensions of homomorphisms on group algebras of abelian groups are extended to the setting of Fourier–Stieltjes algebras of amenable groups. As applications, when G is amenable we provide complete characterizations of those maps between Fourier–Stieltjes algebras that are either associated to a piecewise affine mapping, or are completely bounded and w* – w* continuous.
Bromoform absorption on crystalline polyvinylidene fluoride with 30% of trifluoroethylene, P(VDF-TrFE 70:30) was investigated by photoemission and inverse photoemission and found to be associative and reversible. Molecular bromoform adsorption appears to be an activated process at 120 K with enhanced adsorption following the initial adsorption of bromoform. Strong intermolecular interactions are also implicated in the presence of a weak shake off or screened photoemission final state.
A gambler starts with fortune f < 1 and plays in a Vardi casino with infinitely many tables indexed by their odds, r ≥ 0. In addition, all tables return the same expected winnings per dollar, c < 0, and a discount factor is applied after each round. We determine the optimal probability of reaching fortune 1, as well as an optimal strategy that is different from bold play for fortunes larger than a critical value depending exclusively on c and 1 + a, the discount factor. The general result is computed explicitly for some relevant special cases. The question of whether bold play is an optimal strategy is discussed for various choices of the parameters.