46 research outputs found

    Bent-core liquid crystals joining the ethylene-oxide/lithium ion tandem: Ionic conductivity and dielectric response towards new electrolytes for energy applications

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    We report the dielectric and conductivity response of three materials containing bent-core and tetra(ethylene-oxide) moieties, and their complexes doped with lithium triflate salts, as new potential nanostructured electrolytes. Whilst the pristine bent-core compounds do not show mesomorphism, the doped materials display smectic mesophases inside indium tin oxide cells assisted by the selective solvation of the lithium ions in the ethylene-oxide blocks. The dielectric response of the materials in the high-frequency range is controlled by the chemical composition of the bent-core structure, and the presence of lithium ions promotes direct current conductivity at low frequencies, in the σdc ∼ 10-5 S cm−1 range, which can be enhanced to σdc ∼ 10-4 S cm−1 via trans-to-cis photoisomerization of azobenzene groups. The dynamic and dual character of these materials (responding to low and high frequency electrical fields), the formation of ferroelectric crystals capable to store energy, and their interactions with light, will be applied to develop new energy devices

    Advanced trajectory generator for two carts with RGB-D sensor on circular rail

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    This paper presents a motorised circular rail that generates the motion of two carts with an RGB-D sensor each. The objective of both carts' trajectory generation is to track a person's physical rehabilitation exercises from two points of view and his/her emotional state from one of these viewpoints. The person is moving freely his/her position and posture within the circle drawn by the motorised rail. More specifically, this paper describes the calculation of trajectories for safe motion of the two carts on the motorised circular rail in detail. Lastly, a study case is offered to show the performance of the described control algorithms for trajectory generation.- This work was partially supported by Ministerio de Ciencia, Innovacion y Universidades, Agencia Estatal de Investigacion (AEI) / European Regional Development Fund (FEDER, UE) under DPI2016-80894-R grant

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access

    Half a century of amyloids: past, present and future

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    Amyloid diseases are global epidemics with profound health, social and economic implications and yet remain without a cure. This dire situation calls for research into the origin and pathological manifestations of amyloidosis to stimulate continued development of new therapeutics. In basic science and engineering, the cross-ß architecture has been a constant thread underlying the structural characteristics of pathological and functional amyloids, and realizing that amyloid structures can be both pathological and functional in nature has fuelled innovations in artificial amyloids, whose use today ranges from water purification to 3D printing. At the conclusion of a half century since Eanes and Glenner's seminal study of amyloids in humans, this review commemorates the occasion by documenting the major milestones in amyloid research to date, from the perspectives of structural biology, biophysics, medicine, microbiology, engineering and nanotechnology. We also discuss new challenges and opportunities to drive this interdisciplinary field moving forward. This journal i

    Detection and characterization of TiO2_2 nanomaterials in sludge from wastewater treatment plants of Chihuahua State, Mexico

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    TiO2_2 nanoparticles (TiO2_2-NPs) have a wide range of industrial applications (paintings, sunscreens, food and cosmetics) and is one of the most intensively used nanomaterials worldwide. Leaching from commercial products TiO2_2-NPs are predicted to significantly accumulate in wastewater sludges, which are then often used as soil amendment. In this work, sludge samples from four wastewater treatment plants of the Chihuahua State in Mexico were obtained during spring and summer (2017). A comprehensive characterization study was performed by X-ray based (laboratory and synchrotron) techniques and electron microscopy. Ti was detected in all sludge samples (1810–2760 mg/kg) mainly as TiO2_2 particles ranging from 40 nm up to hundreds of nm. MicroXANES data was analyzed by principal component analysis and linear combination fitting enabling the identification of three predominant Ti species: anatase, rutile and ilmenite. Micro-XANES from the smaller Ti particles was predominantly anatase (68% + 32% rutile), suggesting these TiO2_2-NPs originate from paintings and cosmetics. TEM imaging confirmed the presence of nanoscale Ti with smooth surface morphologies resembling engineered TiO2_2-NPs. The size and crystalline phase of TiO2_2-NPs in the sludge from this region suggest increased reactivity and potential toxicity to agro-systems. Further studies should be dedicated to evaluating this

    Microbial characterization and diversity of artisanal Ranchero cheese with emphasis in Lactococcus strains

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    Abstract The aim of this work is to characterize the natural microflora of artisanal Ranchero cheese and to identify Lactococcus isolates. Ten artisanal Ranchero cheese samples made with raw milk were obtained from local producers located in different geographical areas. Aerobic mesophilic, Staphylococci, Psychrophilic , total coliforms, molds, yeast and, lactic acid bacteria (LAB) (Lactococcus , Streptococcus mesophilic and thermophilic, Lactobacillus , Enterococcus, Leuconostoc) were numbered through agar plating. LAB isolates were classified by genus. Then, nineteen randomly selected presumptive Lactococcus isolates were assigned to specie by PCR amplification and DNA sequence. A high number of aerobic mesophilic Staphylococci, Psychrophilic, total coliforms, molds, and yeast were found. Lactococci, mesophilic and thermophilic Streptococci and Lactobacilli were the dominant LAB. Enterococci and Leuconostoc were also present. The isolates were identified as L. lactis subsp. lactis and L. garvieae . And both were found to be the dominant Lactococcus species that could be selected and used in a starter culture. Sanitation deficiencies in the production of artisanal Ranchero cheese were evident, which may translate into being a potential consumers health risk factor
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