Human immunodeficiency virus (HIV) continues to be a major global public health issue and omnipresent sexually transmitted infections (STIs) increase the risk of HIV acquisition. Moreover, STIs and HIV in pregnant women can harm the unborn child. In this study, we systematically investigated the prevalence of HIV, relevant STIs and vaginal group B streptococcus colonization among pregnant women presenting at Asella Teaching Hospital in central Ethiopia and their effect on perinatal mortality. A follow-up was performed six weeks after delivery. A total of 580 women were included, of which 26.6% tested positive for at least one pathogen ( Chlamydia trachomatis 9.8%, trichomoniasis 5.3%, hepatitis B 5.3%, gonorrhoea 4.3%, group B streptococcus 2.4%, syphilis 2.2%, HIV 2.1%). None of the HIV infections were previously undiagnosed, indicating effective HIV screening activities in the region. Follow-up data were available for 473 (81.6%) children, of which 37 (7.8%) were stillborn or died within the first six weeks of life. Infection with Trichomonas vaginalis and recruitment at obstetric ward (versus antenatal care) were associated with mortality. High prevalence of STIs in pregnant women and their impact on the unborn child demonstrate the need for screening and treatment programmes in order to prevent perinatal mortality.

The bond stretch isomer 1,3-diphosphacyclobutane-2,4-diyl 1 was transformed photochemically to give the previously unknown 2,4-diphosphabicyclo[1.1.0]butane 2, which itself can be converted thermally into gauche-1,4-diphosphabutadiene 3. The crystal structures of these three energy-rich valence isomers of 1,2-diphosphete have been determined. R=SiMe(3); Mes*=2,4,6-tBu(3)C(6)H(2).

Features of the turbulent cascade are investigated for various datasets from three different turbulent flows, namely free jets as well as wake flows of a regular grid and a cylinder. The analysis is focused on the question as to whether fully developed turbulent flows show universal small scale features. Two approaches are used to answer this question. Firstly, 2-point statistics, namely structure functions of longitudinal velocity increments and secondly, joint multi-scale statistics of these velocity increments are analysed. The joint multi-scale characterisation encompasses the whole cascade in one joint probability density function. On the basis of the datasets, evidence of the Markov property for the turbulent cascade is shown, which corresponds to a three point closure that reduces the joint multi-scale statistics to simple conditional probability density functions (cPDF). The cPDF are described by the Fokker-Planck equation in scale and its Kramers-Moyal coefficients (KMCs). KMCs are obtained by a self-consistent optimisation procedure from the measured data and result in a Fokker-Planck equation for each dataset. The knowledge of these stochastic cascade equations enables to make use of the concepts of non-equilibrium thermodynamics and thus to determine the entropy production along individual cascade trajectories. In addition to this new concept, it is shown that the local entropy production is nearly perfectly balanced for all datasets by the integral fluctuation theorem (IFT). Thus the validity of the IFT can be taken as a new law of the turbulent cascade and at the same time independently confirms that the physics of the turbulent cascade is a memoryless Markov process in scale. IFT is taken as a new tool to prove the optimal functional form of the Fokker-Planck equations and subsequently to investigate the question of universality of small scale turbulence in the datasets. The results of our analysis show that the turbulent cascade contains universal and non-universal features. We identify small scale intermittency as a universality breaking feature. We conclude that specific turbulent flows have their own particular multi-scale cascade, with other words their own stochastic fingerprint.

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Based on direct numerical simulations with point-like inertial particles, with Stokes numbers, $\textrm{St}=0, 0.5$, $3$, and $6$, transported by homogeneous and isotropic turbulent flows, we present in this letter for the first time evidence for the existence of Markov property in Lagrangian turbulence. We show that the Markov property is valid for a finite step size larger than a Stokes number-dependent Einstein-Markov coherence time scale. This enables the description of multi-scale statistics of Lagrangian particles by Fokker-Planck equations, which can be embedded in an interdisciplinary approach linking the statistical description of turbulence with fluctuation theorems of non-equilibrium stochastic thermodynamics and local flow structures. The formalism allows estimation of the stochastic thermodynamics entropy exchange associated with the particles’ Lagrangian trajectories. Entropy consuming trajectories of the particles are related to specific evolution of velocity increments through scales and may be seen as intermittent structures. Statistical features of Lagrangian paths and entropy values are thus fixed by the fluctuation theorems.

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