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3D printed concrete is being applied in an increasing amount worldwide. While in theory, there are environmental and economic benefits associated with using this technology, in practice, the amount of cement in printable concrete is much higher than in a conventional one, leading to increased environmental and economic costs. Furthermore, cement's performance relies heavily on climate variables, specifically temperature. One way to solve this issue is to include local alternative low‐CO2 materials, such as processed mine tailings, as cement replacement. This paper presents an experimental approach to assess the use of copper tailings as cement replacement in printable concrete under different ambient temperatures. Three levels of cement volume replacement have been researched. The copper tailings' rheological effect has been measured using standard printability tests and a rheometer. Four mixtures have been printed in a controlled‐climate chamber to evaluate print‐ability, buildability and extrudability. The mechanical effect has been assessed with compressive and flexural strength tests of samples collected from the printed specimens. The results show that copper tailings are a promising alternative to cement in printable concrete in countries where this by‐product is abundant. [ABSTRACT FROM AUTHOR]

The landscape is a tourist attraction of international character that reflects customs, traditions and knowledge with respect to the man-nature relationship; therefore, it contains an endless number of meanings and interpretations. However, there are elements inherent to this activity that threaten its integrity and compromise its value. The objective of this paper is to examine the relationship between sustainable development and the valorization of the landscape within a tourism context. For this purpose, a cabinet analysis is chosen, gathering scientific documents for their analysis and interpretation. The results show that sustainability is an indispensable requirement and a decisive factor for landscape valorization. Likewise, landscape valorization serves as a useful instrument for sustainable development by trying to find a plan that allows preserving such meanings and value. In conclusion, the relationship is reciprocal; they function as flexible drivers to detonate natural and economic benefits, contributing to social welfare and favoring tourism. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM), also referred as 3D printing, is a technology that enables building automated three-dimensional objects in a layer-by-layer manner. AM of cement-based and alkali-activated composites has gathered attention over the last decade and is one of the most rapidly developing civil engineering fields. Development of proper mixture compositions which are suitable in fresh and hardened state is one of the key challenges of AM technology in construction. As the behaviour of cement-based materials (CBM) and alkali-activated materials (AAM) is determined by chemical and physical processes at the nano-level, incorporation of nano- and micro-sized admixtures has great influence on the performance of printable composites. These modifications are attributed to the unique reactivity of nanoparticles associated with their small size and large surface area. This review paper summarizes recent developments in the application of nano- and micro-particles on 3D printable cementitious composites and how they influence the performance of 3D-printed construction materials. The research progress on nano-engineered CBM and AAM is reviewed from the view of fresh and hardened properties. Moreover, comparison between nano- and micro-sized admixtures including nanosilica, graphene-based materials, and clay nanoparticles as well as chemical admixtures such as viscosity-modifying admixtures and superplasticizers is presented. Finally, the existing problems in current research and future perspectives are summarized. This review provides useful recommendations toward the significant influence of nano- and micro-sized admixtures on the performance of 3D printable CBMs. [ABSTRACT FROM AUTHOR]

Introduction: Emphysematous gastritis is an uncommon pathology but with high mortality, its clinical presentation is insidious, the tomography image is distinguished by a pattern of linear bubbles with thickening of the gastric wall. Background: This is a 78-year-old male, previously healthy, functional, who was admitted for pertrochanteric fracture of the left hip, who during hospitalization presented hyperactive delirium, abdominal distention with decreased perstalsis in addition to arterial hypotension, an abdominal tomography with evidence of gastric dilation and multiple air bubbles in the wall. He is managed with a broad spectrum antibiotic, fluid therapy and parenteral nutrition, with a favorable response. Conclusions: Advanced age does not in itself lead to a worse disease prognosis, the evidence supports that early diagnosis and early therapeutic intervention are the measures that have proven to be more effective in reducing mortality in patients with emphysematous gastritis. [ABSTRACT FROM AUTHOR]

Fluorescent photochromic molecules that exhibit distinct light‐triggered changes in their emission colors are highly desirable for the fabrication of smart soft materials and advanced photonic devices. α‐Cyanodiarylethenes, that is, α‐cyano‐functionalized diarylethenes, as alternative "non‐azo" Z/E photochromic molecular switches, are popular choices due to their unique characteristics such as their aggregation‐induced emission or aggregation‐induced‐enhanced emission behavior in their self‐assembled states, and visible changes in fluorescence colors during Z/E photoisomerization. In recent years, the development of fluorescent photochromic α‐cyanodiarylethene‐based compounds including α‐cyanostilbenes, dicyanodistyrylbenzenes, and diaryldicyanoethenes, has mainly focused on molecular design, photochemical and photophysical behavior in solution, and smart soft matter technologies. In this review, recent significant achievements in light‐responsive systems based on the Z/E photoisomerization of fluorescent photochromic α‐cyanodiarylethene switches that span the range from liquid crystals to gels and finally to self‐assembled nanostructures, are highlighted. The smart soft materials constructed from α‐cyanodiarylethene molecular switches find use in a plethora of areas, including display, sensing, encrypting, actuating, and biomedical imaging applications, among others. The review concludes with a brief perspective on some major challenges and opportunities for the future development of light‐responsive smart soft photonic materials. [ABSTRACT FROM AUTHOR]

Copyright of Acta Pediatrica de Mexico is the property of Instituto Nacional de Pediatria (INP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archivos Latinoamericanos de Nutrición is the property of Sociedad Latinoamericana de Nutricion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Adding colloidal nanoparticles into liquid-crystal media has become a promising pathway either to enhance or to introduce novel properties for improved device performance. Here we designed and synthesized new colloidal hybrid silica nanoparticles passivated with a mesogenic monolayer on the surface to facilitate their organo-solubility and compatibility in a liquid-crystal host. The resulting nanoparticles were identified by 1H NMR spectroscopy, TEM, TGA, and UV/Vis techniques, and the hybrid nanoparticles were doped into a dual-frequency cholesteric liquid-crystal host to appraise both their compatibility with the host and the effect of the doping concentration on their electro-optical properties. Interestingly, the silica-nanoparticle-doped liquid-crystalline nanocomposites were found to be able to dynamically self-organize into a helical configuration and exhibit multi-stability, that is, homeotropic (transparent), focal conic (opaque), and planar states (partially transparent), depending on the frequency applied at sustained low voltage. Significantly, a higher contrast ratio between the transparent state and scattering state was accomplished in the nanoparticle-embedded liquid-crystal systems. [ABSTRACT FROM AUTHOR]

Self-organized 3D photonic superstructures loaded with plasmonic hybrid nanorods were found to undergo structural transformation from body-centered cubic to simple cubic upon NIR-light irradiation resulting from the “photothermal effect” of gold nanorods. Furthermore, dynamic NIR light-directed red, green and blue reflections of the nanocomposites were demonstrated. [ABSTRACT FROM AUTHOR]

Light-driven phase transition in liquid crystals is a fascinating endeavour from both scientific and technological points of view. Here we demonstrate the proof-of-principle that the photothermal effect of organo-soluble plasmonic gold nanorods can introduce the phase transition of thermotropic liquid crystals upon near infrared laser irradiation. Interestingly, the reverse process occurs when the laser is switched off. [ABSTRACT FROM AUTHOR]

In this article, we report on the synthesis and thermotropic behaviour of methacrylic polymers containing 4′-(4-alkyloxyphenyl)azobenzene mesogens attached to the backbone throughn-alkyloxy spacers of 6 or 10 methylene groups. Polymerisations were carried out via free radicals using azobisisobutyronitrile (AIBN) as initiator. Chemical structures of polymers and their precursors were characterised by1H NMR spectroscopy. Thermogravimetric analysis showed that azopolymers are thermally stable up to temperatures around 300°C. The thermotropic liquid-crystalline (LC) behaviour was studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and X-ray diffraction (XRD). Results indicate that all synthesised mesogens, monomers and polymers developed two or more orthogonal LC phases in wide temperature ranges. Mesogens and monomers developed nematic and smectic phases, whereas polymers exhibited only smectic phase. In polymers, the arrangement of mesogens depends on the relative length of the spacer and the terminal flexible chain; two distinct structural models were proposed based on chemical interactions and steric constrains. Thetrans–cisphotoisomerisation of monomers and polymers in solution was also studied. Highcis-isomer contents (>80%) were reached in relative short irradiation times despite the steric constrains imposed by the polymer backbone. [ABSTRACT FROM AUTHOR]

Introduction: stevia consumption has increased worlwide among the different age groups; however, studies regarding the association between stevia intake and nutritional status in adults are scarce.Objective: to evaluate stevia intake in first year university students from five chilean cities (Santiago, Temuco, Viña del Mar, Concepción and Antofagasta) controlling by nutritional status, socioeconomic level, gender and whether their undergraduate program belongs to the health sciences.Materials and Methods: 486 first year university students belonging to 4 Chilean universities were evaluated. Each student completed a weekly food frequency questionnaire including food and beverages containing stevia. Selfreport of weight and height was requested.Results: 69.8% of the students consumed stevia every week, the liquid form being the main contributor to the dietary stevia intake (81.2%). Only 1.4% of the students went over the Acceptable Daily Intake (ADI). Normal weight women show a higher stevia intake compared to those obese or overweight (p < 0.05). Finally, stevia consumption appears to be positively associated to normal weight in the first model (adjusted) (OR = 0.219; IC 95%: 0.13-0.35; p < 0.05) and second model (OR = 0.21; IC 95%: 0.13-0.35; p < 0.05).Conclusion: stevia consumption was positively associated with normal nutritional status in Chilean university students. [ABSTRACT FROM AUTHOR]