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An abstract of the article "Pregnancy outcomes of women with mechanical heart valves" by A. Kucuker, E. G. Y. Eyi, S. A. Kucuker, M. Hidiroglu, O. Yurdakok, Z. Catav, A. Kunt and E. Sener is presented.

The long-term outcomes of concomitant cardiovascular procedures in left ventricular assist device (LVAD) surgery are controversial. We report our clinical outcomes of concomitant cardiovascular procedures with LVAD surgery. From January 2013 to August 2022, 220 adult patients (mean age 46±13, male 84%) who underwent LVAD implantation (HeartMate 3 50%; HeartWare 46%; HeartMate II 3%; The ReliantHeart aVAD 1%) with or without concomitant procedures were included. Of the patients, 83% had isolated LVAD implantation, while the other patients (17%) had a concomitant procedure with LVAD implantation. Primary end-point was mortality and secondary end-points were intensive care unit (ICU) stay, and late right ventricular failure (RVF). 37 concomitant procedures were aortic valve replacement with bioprosthesis (37%), tricuspid valve annuloplasty (21%), secundum atrial septal defect repair (16%). Temporary right-sided VAD was required in 8% of patients and Levitronix was implanted. Moreover, coronary artery bypass grafting (5%), LV aneurysmectomy (5%) and carotid endarterectomy (2%) were also performed. Although there was no significant difference between the groups in terms of ICU stay (p=0.367) and late RVF (p=0.732), the mortality of concomitant procedures with LVAD was higher than that of isolated LVAD (log-rank: 0.034) in long-term follow-up (Figure 1). Concomitant procedures with LVAD appear to increase mortality in long-term. [ABSTRACT FROM AUTHOR]

We study the reaction channels 7Li+γ → n + 6Li(2.19), 7Li+γ → n + 6Li(3.56), and 7Li+γ → d + 5He(1.27) → n +d + 4He by detecting neutrons produced by photodisintegration events. We find absolute cross sections and angular dependence for 7Li+γ → n + 6Li(2.19) at photon energies 13 and 15 MeV and for 7Li + γ → n + 6Li(3.56) at the photon energy 15 MeV. The incident photons are linearly polarized and we report dependence of the cross sections on polarization. For the reaction channel 7Li + γ → d + 5He(1.27) → n + d + 4He we obtain an upper bound on its cross section at photon energies 12, 13, and 15 MeV. [ABSTRACT FROM AUTHOR]

Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσ/dΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also a widely used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. We describe our measurements and compare them with previous work. [ABSTRACT FROM AUTHOR]

The cross sections for the photodisintegration of 6Li have been measured for all the available reaction channels that have neutrons in the final state, except the 6Li(γ,pO ) 5He(g.s.) channel. The cross sections were measured at the photon energies, 8, 9, 10, 11, 12, 13, 15, and 15.6 MeV using linearly polarized photons, and 20, 25, 30, and 35 MeV using circularly polarized photons. Associated Legendre function coefficients are extracted for the 6Li(γ,no )5Li (g.s.) and 6Li(γ,n1) 5Li(1.49) channels. For all observed reaction channels Legendre function parametrizations are used to determine total cross sections. Comparisons with recent theoretical calculations of the total photodisintegration cross section using various nucleon-nucleon interactions are inconclusive because of the large uncertainty in the cross sections for reactions channels that are not measured. We hope that the precision of our results for specific reaction channels will prompt calculations for those reaction channels. [ABSTRACT FROM AUTHOR]

We have measured the cross section of the photoneutron reaction channel 7Li + γ → 6Li(g.s.) + n where the progeny nucleus is the ground state of 6Li. We obtained the absolute cross section at photon energies 10, 11, 12, 13, 15, 20, 25, 30, and 35 MeV and also the dependence of the cross section on polar angle for all but the highest photon energy. For the energies 10 to 15 MeV we were able to use linearly polarized photons to obtain the dependence of the cross section on the photon polarization. [ABSTRACT FROM AUTHOR]

Introduction:  Placental insufficiency is one of the reasons for the reduction of hormone production. Thus, if one of the suspected causes of hypospadias is placental insufficiency, then the neurodevelopmental status of boys with hypospadias may be impaired. The aim of this study was to evaluate the neurodevelopmental status of boys with hypospadias and guide the parents of those who need support to related departments for early intervention., Materials and Methods:  Boys were divided into two groups, those with hypospadias (group H) and healthy children undergoing traditional circumcision (group C). The parents of the boys completed the Ages and Stages Questionnaire (ASQ) and ASQ-Social Emotional (SE), both of which are screening instruments for the early identification of developmental and social-emotional problems, respectively., Results:  Seventy-eight boys had hypospadias and 59 were admitted for traditional circumcision. The group H had statistically significant more impaired scores than group C in communication, gross motor, and personal-social skill sections. The multivariate logistic regression analysis revealed that hypospadias was the independent predictive factor for communication and personal-social skills., Conclusion:  Hypospadias and neurologic impairment may share common etiologic factors. Accordingly, physicians should keep in mind that if a boy presents with hypospadias, the possibility of having neurologic impairment is higher than normal population and early intervention has crucial importance. Every boy with hypospadias should be evaluated for neurodevelopmental status., Competing Interests: None declared., (Thieme. All rights reserved.)

Objectives: Betanin and copper sulphate have been previously indicated as beneficial agents for ischemia/reperfusion (I/R) as antioxidant compounds in various models. We investigated whether betanin and copper have any protective effects on the heart and lung against I/R injury in rats., Methods: Spraque-Dawley rats were assigned in groups: Sham (laparotomy only), control (I/R only), betanin treatment (100 mg/kg of betanin administered intraperitoneally (i.p.) 60 minutes before I/R) and copper sulfate treatment group (0.1 mg/kg/day copper sulfate i.p. for 7 days before I/R). Ischemia was induced by clamping the aorta between the left renal artery and aortic bifurcation for 45 minutes. After 48-hour reperfusion, the rats were sacrificed and heart/lung tissues were harvested. Malondialdehyde (MDA), myeloperoxidase (MPO), interleukin 6 (IL-6) levels were determined. Apoptosis was determined via TUNEL assay., Results: MDA, MPO, IL-6 levels and apoptotic cells were significantly increased in the I/R group. In both treatment groups, MDA and MPO levels were decreased. IL-6 was significantly decreased in response to betanin administration in the heart, but not in the lung; copper had no effect in either area. The numbers of apoptotic cells were significantly decreased in both treatment groups., Conclusion: Betanin and copper may have protective effects on I/R injury in the heart and lung in rats (Fig. 6, Ref. 39).

We report the first observation of the parity-violating gamma-ray asymmetry A_{γ}^{np} in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target at the Spallation Neutron Source at Oak Ridge National Laboratory. A_{γ}^{np} isolates the ΔI=1, ^{3}S_{1}→^{3}P_{1} component of the weak nucleon-nucleon interaction, which is dominated by pion exchange and can be directly related to a single coupling constant in either the DDH meson exchange model or pionless effective field theory. We measured A_{γ}^{np}=[-3.0±1.4(stat)±0.2(syst)]×10^{-8}, which implies a DDH weak πNN coupling of h_{π}^{1}=[2.6±1.2(stat)±0.2(syst)]×10^{-7} and a pionless EFT constant of C^{^{3}S_{1}→^{3}P_{1}}/C_{0}=[-7.4±3.5(stat)±0.5(syst)]×10^{-11}  MeV^{-1}. We describe the experiment, data analysis, systematic uncertainties, and implications of the result.

We report new measurements of inclusive pi production from frozen-spin HD for polarized photon beams covering the Delta(1232) resonance. These provide data simultaneously on both H and D with nearly complete angular distributions of the spin-difference cross sections entering the Gerasimov-Drell-Hearn (GDH) sum rule. Recent results from Mainz and Bonn exceed the GDH prediction for the proton by 22 microb, suggesting as yet unmeasured high-energy components. Our pi0 data reveal a different angular dependence than assumed in Mainz analyses and integrate to a value that is 18 microb lower, suggesting a more rapid convergence. Our results for deuterium are somewhat lower than published data, considerably more precise, and generally lower than available calculations.

Background and Aim of the Study: Cardiac surgery during pregnancy represents a major challenge as it comprises a single operation for two survivors., Methods: Between 1988 and 2005, 16 pregnant women underwent cardiac surgery at the authors' institution. Among 14 patients with rheumatic mitral stenosis operated on due to clinical deterioration, closed mitral valvulotomy was performed in 12 cases (three urgently in the third trimester, nine at term concomitantly with cesarean delivery). Two patients underwent mitral valve replacement, again, concomitantly with cesarean delivery at term, while two others underwent emergency reoperation for mechanical valve thrombosis during the second trimester, using a strategy of high-flow, high-pressure perfusion with mild hypothermia., Results: A total of 12 closed mitral valvulotomies and four mitral valve replacements was performed. There was no maternal mortality, and only one stillborn occurred in the urgent closed valvulotomy group. The remaining 15 babies were born healthy., Conclusion: In addition to protective perinatal procedures, instances occur during pregnancy when urgent or emergency surgery becomes unavoidable due to life-threatening cardiac decompensation. In patients with mitral stenosis, which is the case in most scenarios, closed mitral valvulotomy is life-saving and offers low fetomaternal risk, as a viable, efficient and practical alternative to percutaneous mitral balloon commissurotomy. When cardiopulmonary bypass (CPB) becomes mandatory, the shortest possible periods of mildly hypothermic or normothermic CPB with a strategy of high flow-high pressure perfusion should be followed.