1,431 research outputs found

    5,5′-Bis[(2,2,2-trifluoro­eth­oxy)meth­yl]-2,2′-bipyridine

    Get PDF
    The complete molecule of the title compound, C16H14F6N2O2, is generated by crystallographic inversion symmetry, which results in two short intramolecular C—H⋯N hydrogen-bond contacts per molecule. In the crystal, aromatic π–π stacking [centroid–centroid distance = 3.457 (2) Å] and weak C—H⋯π inter­actions occur. A short H⋯H [2.32 (3) Å] contact is present

    Taiji Data Challenge for Exploring Gravitational Wave Universe

    Full text link
    The direct observation of gravitational waves (GWs) opens a new window for exploring new physics from quanta to cosmos and provides a new tool for probing the evolution of universe. GWs detection in space covers a broad spectrum ranging over more than four orders of magnitude and enables us to study rich physical and astronomical phenomena. Taiji is a proposed space-based GW detection mission that will be launched in the 2030s. Taiji will be exposed to numerous overlapping and persistent GW signals buried in the foreground and background, posing various data analysis challenges. In order to empower potential scientific discoveries, the Mock LISA Data Challenge and the LISA Data Challenge (LDC) were developed. While LDC provides a baseline framework, the first LDC needs to be updated with more realistic simulations and adjusted detector responses for Taiji's constellation. In this paper, we review the scientific objectives and the roadmap for Taiji, as well as the technical difficulties in data analysis and the data generation strategy, and present the associated data challenges. In contrast to LDC, we utilize second-order Keplerian orbit and second-generation time delay interferometry techniques. Additionally, we employ a new model for the extreme-mass-ratio inspiral waveform and stochastic GW background spectrum, which enables us to test general relativity and measure the non-Gaussianity of curvature perturbations. Furthermore, we present a comprehensive showcase of parameter estimation using a toy dataset. This showcase not only demonstrates the scientific potential of the Taiji Data Challenge but also serves to validate the effectiveness of the pipeline. As the first data challenge for Taiji, we aim to build an open ground for data analysis related to Taiji sources and sciences. More details can be found on the official website at http://taiji-tdc.ictp-ap.org.Comment: 15 pages, 3 figure

    Global prevalence of WHO infant feeding practices in 57 LMICs in 2010-2018 and time trends since 2000 for 44 LMICs

    Get PDF
    BackgroundThe World Health Assembly set a global target of increasing exclusive breastfeeding for infants under 6 months to at least 50% by year 2025. However, little is known about the current status of breastfeeding practice, as well as the trends in breastfeeding practices during recent years. We examined global prevalence of the World Health Organization (WHO) feeding practices in 57 low- and middle-income countries (LMICs) and time trends since 2000 for 44 selected countries.MethodsWe included 57 eligible LMICs that had completed data on breastfeeding and complementary feeding in 2010–2018 from the Demographic and Health Surveys (DHS) for examining current feeding status. We further selected 44 LMICs that had two standard DHS surveys between 2000 and 2009 and 2010–2018 to examine time trends of feeding status. We calculated global, regional, and national weighted prevalence estimates and 95% confidence intervals (CIs) for five breastfeeding indicators and two complementary feeding indicators.FindingsIn 57 LMICs during 2010–2018, global weighted prevalence was 51.9% for early initiation of breastfeeding, 45.7% for exclusive breastfeeding under 6 months, 32.0% for exclusive breastfeeding at 4–5 months, 83.1% for continued breastfeeding at 1 year, 56.2% for continued breastfeeding at 2 years, 14.9% for introduction of solid, semi-solid or soft foods under 6 months, and 63.1% for introduction of solid, semi-solid or soft foods at 6–8 months. Eastern Mediterranean (34.5%) and European regions (43.7%) (vs. South-East Asia/Western Pacific (55.2%)), and upper middle-income countries (38.4%) (vs. lower middle-income countries (47.4%)) had poorer performance of exclusive breastfeeding under 6 months. South-East Asia/Western Pacific regions (51.0%) (vs. other regions (68.3%-84.1%)) and low-income (66.4%) or lower middle-income countries (58.2%) (vs. upper middle-income countries (81.7%)) had lower prevalence of introduction of solid, semi-solid or soft foods at 6–8 months. In 44 selected LMICs from 2000 to 2009 to 2010–2018, total weighted prevalence presented an increase of 10.1% for exclusive breastfeeding under 6 months, but a 1.7% decrease for continued breastfeeding at 1 year. Over this period, the Eastern Mediterranean region had a 5.3% decrease of exclusive breastfeeding under 6 months, and the European region had a 2.0% increase for introduction of solid, semi-solid or soft foods under 6 months. The prevalence of introduction of solid, semi-solid or soft foods at 6–8 months decreased in South-East Asia/Western Pacific region by 15.2%, and in lower middle-income countries by 24.4%.InterpretationBreastfeeding practices in LMICs have continued to improve in the past decade globally, but practices still lag behind the WHO feeding recommendations. Breastfeeding practices differed greatly across WHO regions, with the Eastern Mediterranean and European regions, and upper middle-income countries facing the greatest challenges in meeting targets. Continued efforts are needed to achieve the 2025 global breastfeeding target.</p

    MicroRNA-9 expression is a prognostic biomarker in patients with osteosarcoma

    Full text link

    Radiology-guided forceps biopsy and airway stenting in severe airway stenosis

    Get PDF
    PURPOSEWe aimed to determine the feasibility, safety, and effectiveness of radiology-guided forceps biopsy and airway stenting in patients with severe airway stenosis.MATERIALS AND METHODSThis study involved 28 patients with severe airway stenosis who underwent forceps biopsy between October 2006 and September 2011. Chest multislice computed tomography was used to determine the location and extent of stenosis. Sixteen patients had tracheal stenosis, two patients had stenosis of the tracheal carina, six patients had stenosis of the left main bronchus, and four patients had stenosis of the right main bronchus. Forceps biopsy and stenting of the stenosed area were performed under fluoroscopic guidance in digital subtraction angiography and the biopsy specimens were analyzed histopathologically. We contacted the patients via phone call and utilized a standardized questionnaire to determine their medical condition during a postoperative three-month follow-up.RESULTSThe technical success rate of radiology-guided forceps biopsy was 100%. Biopsy specimens were obtained in all patients. Dyspnea was relieved immediately after stent placement. No serious complications, such as tracheal hemorrhage or perforation, mediastinal emphysema, or asphyxia, occurred.CONCLUSIONRadiology-guided forceps biopsy and airway stenting can be used for the emergency treatment of severe airway stenosis. This method appears to be safe and effective, and it may be an alternative therapeutic option in patients who cannot tolerate fiberoptic bronchoscopy

    Epidemiological characteristics analysis of foodborne disease outbreaks caused by takeaway in China’s Mainland from 2010 to 2020

    Get PDF
    ObjectiveTo analyze the epidemiological characteristics of foodborne disease outbreaks caused by takeaway in China’s Mainland from 2010 to 2020, and put forward relevant regulatory suggestions.MethodsThrough the National Foodborne Disease Outbreak Monitoring System, the data of foodborne disease outbreaks caused by takeaway in China’s Mainland from 2010 to 2020 were collected and analyzed, and descriptive epidemiological characteristics were performed.ResultsA total of 549 foodborne disease outbreaks caused by takeaway were reported in China’s Mainland (except Tibet Autonomous Region) from 2010 to 2020, resulting in 9 285 illnesses and 2 deaths. The largest number of outbreaks and illnesses was in the third quarter, accounting for 41.53% and 44.58% of the total respectively. Except the unknown pathogenic factors, the number of outbreaks and illnesses caused by microbial pathogenic factors were the highest, accounting for 39.16% and 60.26% of the total respectively. Except the unknown suspected food, the number of outbreaks and illnesses caused by mixed food and multiple food were higher, accounting for 21.86% and 15.12% of the outbreaks respectively, and accounting for 20.58% and 13.10% of the number of illnesses respectively. Except the unknown food source, the top 3 food source were school canteens, collective dining delivery units/central kitchens and fast food restaurants, the number of outbreaks accounted for 20.04%, 15.66% and 15.48% respectively, and the number of illnesses accounted for 35.30%, 17.52% and 10.57% respectively. Except the multiple factors and unknown factors, the number of outbreaks caused by improper storage were the highest accounting for 8.74%, and the number of illnesses caused by improper processing accounted for 7.74%.ConclusionMicrobial growth and reproduction due to improper storage and processing is the major cause of foodborne disease outbreaks caused by takeaway. It is suggested that the food safety supervision and administration departments should strengthen the whole process supervision and management of takeaway, establish and ensure catering services strictly abide by the good hygiene operations according to food raw in materials, production, transportation, distribution and other aspects, so as to effectively prevent and control the occurrence foodborne diseases

    MoO3 nanoparticle coatings on high-voltage 5 V LiNi0.5 Mn1.5 O4 cathode materials for improving lithium-ion battery performance

    Get PDF
    To reduce surface contamination and increase battery life, MoO3 nanoparticles were coated with a high-voltage (5 V) LiNi0.5 Mn1.5 O4 cathode material by in-situ method during the high-temperature annealing process. To avoid charging by more than 5 V, we also developed a system based on anode-limited full-cell with a negative/positive electrode (N/P) ratio of 0.9. The pristine LiNi0.5 Mn1.5 O4 was initially prepared by high-energy ball-mill with a solid-state reaction, followed by a precipitation reaction with a molybdenum precursor for the MoO3 coating. The typical structural and electrochemical behaviors of the materials were clearly investigated and reported. The results revealed that a sample of 2 wt.% MoO3-coated LiNi0.5 Mn1.5 O4 electrode exhibited an optimal electrochemical activity, indicating that the MoO3 nanoparticle coating layers considerably enhanced the high-rate charge–discharge profiles and cycle life performance of LiNi0.5 Mn1.5 O4 with a negligible capacity decay. The 2 wt.% MoO3-coated LiNi0.5 Mn1.5 O4 electrode could achieve high specific discharge capacities of 131 and 124 mAh g−1 at the rates of 1 and 10 C, respectively. In particular, the 2 wt.% MoO3-coated LiNi0.5 Mn1.5 O4 electrode retained its specific capacity (87 mAh g−1) of 80.1% after 500 cycles at a rate of 10 C. The Li4 Ti5 O12 /LiNi0.5 Mn1.5 O4 full cell based on the electrochemical-cell (EL-cell) configuration was successfully assembled and tested, exhibiting excellent cycling retention of 93.4% at a 1 C rate for 100 cycles. The results suggest that the MoO3 nano-coating layer could effectively reduce side reactions at the interface of the LiNi0.5 Mn1.5 O4 cathode and the electrolyte, thus improving the electrochemical performance of the battery system
    corecore