356 research outputs found

    Optimal conditions for tissue growth and branch induction of Gracilariopsis persica

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    The species Gracilariopsis persica was first described by Bellorin et al. (2008). G. persica grows from late September to July and shows high growth rate from January to May in the Persian Gulf. Tissue growth and branch induction of red seaweed, Gracilariopsis persica from the Persian Gulf investigated under various culture levels of temperature, light intensity, photoperiod, salinity, initial length, propagule density and chemical preservatives. Optimal size of propagules used as seed was 2 cm and faster growth of tissue and branch induction obtained at lower density. The apical part of the G. persica showed as the starting point of growth. The G. persica showed optimal growth in PES medium at 24°C, 60μmol m-2 s-1 light intensity, 12L: 12D and salinity of 39‰. But maximum branch production occurred under condition of 24°C, 20 μmol m-2 s-1 light intensity, photoperiod of 16L: 8D and salinity 39‰. Addition of chemical preservatives of p-hydroxybenzoic acid and potassium sorbate in culture medium showed marginal suppression on tissue growth and branch induction, that suitable for preparation of semi-axenic culture condition

    Effect of Floor Space Allowance on Pig Productivity across Stages of Growth: A Field-scale Analysis

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    A total of 152 pig farms were randomly selected from the five provinces in South Korea. During the experiment, the average temperature and relative humidity was 24.7°C and 74% in summer and 2.4°C and 53% in winter, respectively. The correlation between floor space allowance (FSA) and productivity index was analyzed, including non-productive sow days (NPD), number of weaners (NOW), survival rate (SR), appearance rate of A-grade pork (ARA), and days at a slaughter weight of 110 kg (d-SW) at different growth stages. The objectives of the present study were i) to determine the effect of FSA on the pig productivity index and ii) to suggest the minimum FSA for pigs based on scientific baseline data. For the pregnant sow, NPD could be decreased if pregnant sows were raised with a medium level (M) of FSA (3.10 to 3.67 m2/head) while also keeping the pig house clean which improves hygiene, and operating the ventilation system properly. For the farrowing sows, the NOW tended to decrease as the FSA increased. Similarly, a high level of FSA (H) is significantly negative with weaner SR of farrowing sows (p-value = 0.017), indicating this FSA tends to depress SR. Therefore, a FSA of 2.30 to 6.40 m2/head (very low) could be appropriate for weaners because a limited space can provide a sense of security and protection from external interruptions. The opposite trend was observed that an increase in floor space (>1.12 m2/head) leads to increase the SR of growing pigs. For the fattening pigs, H level of FSA was negatively correlated with SR, but M level of FSA was positively correlated with SR, indicating that SR tended to increase with the FSA of 1.10 to 1.27 m2/head. In contrast, ARA of male fattening pigs showed opposite results. H level of FSA (1.27 to 1.47 m2/head) was suggested to increase productivity because ARA was most affected by H level of space allowance with positive correlation (R2 = 0.523). The relationship between the FSA and d-SW of fattening pigs was hard to identify because of the low R2 value. However, the farms that provided a relatively large floor space (1.27 to 1.54 m2/head) during the winter period showed d-SW was significantly and negatively affected by FSA

    Nano-ilmenite FeTiO3 : synthesis and characterization

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    In general, ilmenite FeTiO3 is synthesized by solid-state reaction at very high pressure and high temperature. Synthesis of FeTiO3 is not an easy task as the Fe2+ ions are not stable. Therefore, it is really challenging to prepare this material. In this work nano-ilmenite FeTiO3 was synthesized by the sol-gel method. Structural, optical and magnetic characterizations were performed. The bandgap of FeTiO3 was determined to be 2.8 eV showing FeTiO3 as suitable wide bandgap material for technological applications. The FeTiO3 nanoparticles exhibit weak ferromagnetic properties at and below room temperature. The Neel temperature was observed to be around 52 K.Fundação para a Ciência e a Tecnologia (FCT

    First-Principles Calculation of the Superconducting Transition in MgB2 within the Anisotropic Eliashberg Formalism

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    We present a study of the superconducting transition in MgB2 using the ab-initio pseudopotential density functional method and the fully anisotropic Eliashberg equation. Our study shows that the anisotropic Eliashberg equation, constructed with ab-initio calculated momentum-dependent electron-phonon interaction and anharmonic phonon frequencies, yields an average electron-phonon coupling constant lambda = 0.61, a transition temperature Tc = 39 K, and a boron isotope-effect exponent alphaB = 0.31 with a reasonable assumption of mu* = 0.12. The calculated values for Tc, lambda, and alphaB are in excellent agreement with transport, specific heat, and isotope effect measurements respectively. The individual values of the electron-phonon coupling lambda(k,k') on the various pieces of the Fermi surface however vary from 0.1 to 2.5. The observed Tc is a result of both the raising effect of anisotropy in the electron-phonon couplings and the lowering effect of anharmonicity in the relevant phonon modes.Comment: 4 pages, 3 figures, 1 tabl

    Effectiveness of revascularisation of the ulcerated foot in patients with diabetes and peripheral artery disease: A systematic review

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    In patients with diabetes, foot ulceration and peripheral artery disease (PAD), it is often difficult to determine whether, when and how to revascularise the affected lower extremity. The presence of PAD is a major risk factor for non-healing and yet clinical outcomes of revascularisation are not necessarily related to technical success. The International Working Group of the Diabetic Foot updated systematic review on the effectiveness of revascularisation of the ulcerated foot in patients with diabetes and PAD is comprised of 64 studies describing >13000 patients. Amongst 60 case series and 4 non-randomised controlled studies, we summarised clinically relevant outcomes and found them to be broadly similar between patients treated with open vs endovascular therapy. Following endovascular revascularisation, the 1 year and 2 year limb salvage rates were 80% (IQR 78-82%) and 78% (IQR 75-83%), whereas open therapy was associated with rates of 85% (IQR 80-90%) at 1 year and 87% (IQR 85-88%) at 2years, however these results were based on a varying combination of studies and cannot therefore be interpreted as cumulative. Overall, wound healing was achieved in a median of 60% of patients (IQR 50-69%) at 1 year in those treated by endovascular or surgical therapy, and the major amputation rate of endovascular vs open therapy was 2% vs 5% at 30days, 10% vs 9% at 1 year and 13% vs 9% at 2years. For both strategies, overall mortality was found to be high, with 2% (1-6%) perioperative (or 30day) mortality, rising sharply to 13% (9-23%) at 1 year, 29% (19-48%) at 2years and 47% (39-71%) at 5years. Both the angiosome concept (revascularisation directly to the area of tissue loss via its main feeding artery) or indirect revascularisation through collaterals, appear to be equally effective strategies for restoring perfusion. Overall, the available data do not allow us to recommend one method of revascularisation over the other and more studies are required to determine the best revascularisation approach in diabetic foot ulceration.Peer reviewe

    The Nancy Grace Roman Space Telescope Coronagraph Instrument (CGI) technology demonstration

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    The Coronagraph Instrument (CGI) on the Nancy Grace Roman Space Telescope will demonstrate the highcontrast technology necessary for visible-light exoplanet imaging and spectroscopy from space via direct imaging of Jupiter-size planets and debris disks. This in-space experience is a critical step toward future, larger missions targeted at direct imaging of Earth-like planets in the habitable zones of nearby stars. This paper presents an overview of the current instrument design and requirements, highlighting the critical hardware, algorithms, and operations being demonstrated. We also describe several exoplanet and circumstellar disk science cases enabled by these capabilities. A competitively selected Community Participation Program team will be an integral part of the technology demonstration and could perform additional CGI observations beyond the initial tech demo if the instrument performance warrants it

    Effects of Magnetovolume and Spin-orbit Coupling in the Ferromagnetic Cubic Perovskite BaRuO3

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    BaRuO3 having five different crystal structures has been synthesized by varying the pressure while sintering. Contrary to the other phases being nonmagnetic, the cubic perovskite phase synthesized recently shows an itinerant ferromagnetic character. We investigated this ferromagnetic BaRuO3 using first principles calculations. A few van Hove singularities appear around the Fermi energy, causing unusually high magnetovolume effects of ΔM/Δa\Delta M/\Delta a ~ 4.3 μB\mu_B/\AA as well as a Stoner instability [IN(0) ~ 1.2]. At the optimized lattice parameter a, the magnetic moment M is 1.01 μB\mu_B in the local spin density approximation. When spin-orbit coupling is included, the topologies of some Fermi surfaces are altered, and the net moment is reduced by 10% to a value very close to the experimentally observed value of ~ 0.8 μB\mu_B. Our results indicate that this ferromagnetism is induced by the Stoner instability, but the combined effects of the p-d hybridization, the magnetovolume, and the spin-orbit coupling determine the net moment. In addition, we briefly discuss the results of the tight-binding Wannier function technique.Comment: 5 pages and 5 embedded figures; proceedings of ICM 201

    Prognostic Implications of Fractional Flow Reserve After Coronary Stenting:A Systematic Review and Meta-analysis

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    IMPORTANCE: Fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is generally considered to reflect residual disease. Yet the clinical relevance of post-PCI FFR after drug-eluting stent (DES) implantation remains unclear. OBJECTIVE: To evaluate the clinical relevance of post-PCI FFR measurement after DES implantation. DATA SOURCES: MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched for relevant published articles from inception to June 18, 2022. STUDY SELECTION: Published articles that reported post-PCI FFR after DES implantation and its association with clinical outcomes were included. DATA EXTRACTION AND SYNTHESIS: Patient-level data were collected from the corresponding authors of 17 cohorts using a standardized spreadsheet. Meta-estimates for primary and secondary outcomes were analyzed per patient and using mixed-effects Cox proportional hazard regression with registry identifiers included as a random effect. All processes followed the Preferred Reporting Items for Systematic Review and Meta-analysis of Individual Participant Data. MAIN OUTCOMES AND MEASURES: The primary outcome was target vessel failure (TVF) at 2 years, a composite of cardiac death, target vessel myocardial infarction (TVMI), and target vessel revascularization (TVR). The secondary outcome was a composite of cardiac death or TVMI at 2 years. RESULTS: Of 2268 articles identified, 29 studies met selection criteria. Of these, 28 articles from 17 cohorts provided data, including a total of 5277 patients with 5869 vessels who underwent FFR measurement after DES implantation. Mean (SD) age was 64.4 (10.1) years and 4141 patients (78.5%) were men. Median (IQR) post-PCI FFR was 0.89 (0.84-0.94) and 690 vessels (11.8%) had a post-PCI FFR of 0.80 or below. The cumulative incidence of TVF was 340 patients (7.2%), with cardiac death or TVMI occurring in 111 patients (2.4%) at 2 years. Lower post-PCI FFR significantly increased the risk of TVF (adjusted hazard ratio [HR] per 0.01 FFR decrease, 1.04; 95% CI, 1.02-1.05; P < .001). The risk of cardiac death or MI also increased inversely with post-PCI FFR (adjusted HR, 1.03; 95% CI, 1.00-1.07, P = .049). These associations were consistent regardless of age, sex, the presence of hypertension or diabetes, and clinical diagnosis. CONCLUSIONS AND RELEVANCE: Reduced FFR after DES implantation was common and associated with the risks of TVF and of cardiac death or TVMI. These results indicate the prognostic value of post-PCI physiologic assessment after DES implantation
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