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Background: Guayulins comprise a family of sesquiterpene compounds with potential industrial applications that are extracted from the resinous fraction of the guayule plant (Parthenium argentatum, A. Gray). If a whole industry is to be developed around guayulins, not only their activity should be assessed, but also their stability because the quality of the final products is likely influenced by the time that elapses from harvesting to processing. Thus, the aim of the present study was to evaluate the stability of guayulin compounds from harvested guayule stems or extracted resin after storage at different temperatures to find in which form, stems or resin, is the storage better. Results: Results showed that, once extracted, the resin could be stored at 20-25 °C for 3 months or more without significant losses of guayulin content. In the case of harvested stems, however, the findings were more complex, with guayulins A and B degrading over time and guayulins C and D showing enrichment. In addition, analysis of the thermal and thermo-oxidative degradation of the resin and guayulins showed that while guayulins A and B showed a maximum decomposition rate around 280 °C, guayulins C and D decomposed at 245 °C. Such thermal differences might be attributed to the observed oxidation of guayulin A and B standards into guayulin C and D, respectively. Conclusion: These findings provide, for the first time, information on the stability of guayulins after harvesting and resin extraction, which could help to the development of an integral industrial process from harvesting to commercializing. [ABSTRACT FROM AUTHOR]

Background: Autosomal dominant mutations in the coatomer-associated protein alpha (COPA) gene cause an immune dysregulation disorder associated with pulmonary hemorrhage, lymphoid hyperplasia, arthritis, and glomerulonephritis. Objective: To describe the thoracic, musculoskeletal, and renal imaging findings of COPA syndrome with a focus on the evolution of the pulmonary findings. Materials and methods: With approval of the Institutional Review Board, consensus retrospective review of findings on chest radiography and computed tomography (CT), musculoskeletal radiography and magnetic resonance imaging (MRI), and renal ultrasound (US) was performed for pediatric COPA syndrome patients. COPA syndrome patients < 18 years of age presenting between 1992 and 2019 were identified from an institutional rheumatology registry. Results: Twelve pediatric COPA syndrome patients (mean age of 6.5 years at first imaging exam; 6 females) were identified. Imaging exams available for review included 45 chest CT exams on 12 patients, 37 musculoskeletal exams on 4 patients, and 10 renal US exams on 5 patients. All 12 had abnormal chest CT exams, with findings including ground-glass opacities (12/12), cysts (8/12), septal thickening (9/12), nodules (8/12), fibrosis (7/12), crazy-paving (2/12), consolidation (1/12), hilar/mediastinal lymphadenopathy (11/12), and chest wall deformity (5/12). Nine had at least one follow-up chest CT, which showed improvement in nodules (7/9), ground-glass opacities (4/9), and lymphadenopathy (9/9), but worsening of septal thickening (3/9), cyst formation (3/9), and fibrosis (3/9). Four had musculoskeletal imaging revealing synovitis (2/4), bone erosions (1/4), tenosynovitis (1/4), enthesitis (1/4), and subcutaneous nodules (1/4). Five had at least one renal US, revealing renal size abnormalities (4/5) and cortical hyperechogenicity (3/5). Conclusion: The most prevalent imaging finding of COPA syndrome is diffuse lung disease related to early childhood-onset recurrent pulmonary hemorrhage and lymphoid hyperplasia that may progress to pulmonary fibrosis. Other imaging findings manifesting later in childhood or adolescence relate to arthritis and glomerulonephritis. [ABSTRACT FROM AUTHOR]

As the number of childhood cancer survivors increases, a heightened awareness and recognition of therapy-related late effects is becoming more important. Pulmonary complications are the third leading cause of late mortality in cancer survivors. Diagnosis of these complications on chest imaging helps facilitate prompt treatment to mitigate adverse outcomes. In this review, we summarize the imaging of late pulmonary complications of cancer therapy in children and highlight characteristic findings that should be recognized by radiologists. [ABSTRACT FROM AUTHOR]

Background: There is still little information about the long-term results of clinical and radiological evolution in patients older than 65 years with complex proximal humerus fractures (CPHF) treated acutely with reverse shoulder arthroplasty (RSA). The aim of this paper was to evaluate function and results 7 years after surgery.Material and Methods: A prospective cross-sectional cohort study was designed for this purpose. Patients who underwent RSA surgery during 2012 because of a CPHF were included. The surgical approach was randomized (deltopectoral vs anterosuperior). Functional activity, evolution of tuberosities and evidence of scapular notching 7 years after surgery were analyzed.Results: After evaluating 32 patients, the Constant score improved from 64.83 in the first year to 69.54 at 7 years postoperative. Results were independent of the approach used. Functional outcomes were poorer in patients with scapular notching and when tuberosities were resorbed or displaced.Conclusions: At 7 years, function in patients undergoing RSA after CPHF demonstrated improvement in all patients except those who developed scapular notching or when tuberosities did not consolidate in an anatomical position. These results are completely independent of the approach used.Level Of Evidence: III Controlled cohort study. [ABSTRACT FROM AUTHOR]

Thermoregulating microcapsules (MC) with flame-retardant properties were used to produce polyurethane (PU) foams. Thermogravimetric analyses of the microcapsules performed under atmospheric air and nitrogen confirmed that the hexa(methacryloylethylenedioxy) cyclotriphosphazene (PNC-HEMA) monomer raised the amount of residue after exposure to high temperature, proving the formation of a thermally stable char layer. Additionally, the flame-retardant properties of the microcapsules were analyzed by micro-combustion calorimetry (MCC), and the PU foams were tested by both MCC and cone calorimetry. The total heat release and maximum heat release rate were lower for microcapsules containing the flame-retardant PNC-HEMA. The composition of the microcapsules has been proved by MCC and TGA, where the release of the encapsulated phase change material (PCM) occurred at the expected temperature. However, in PU foams, the release of PCM is shifted to higher temperatures. Accordingly, these materials can be considered as an important alternative to commonly used microcapsules containing phase PCMs, where a lower flammability is required for their future application. [ABSTRACT FROM AUTHOR]

Slurries with low viscosity and polystyrene (PS) nanoparticle concentration up to 52 wt.% have been synthesized in one-step process with no waste generation, by suspension polymerization and optimizing the concentration of dispersants (sodium dodecyl sulfate, SDS, and the cosurfactant, CS). The CS was manufactured in situ from tetraethyl orthosilicate (TEOS) and vinyltriethoxysilane (VTES). The incorporation of the CS on the PS polymer was confirmed by FT-IR, EDS, and TGA, observing the functionalization of PS nanoparticles with SiOH. Morphology and particle size of the dispersed solid, together with viscosity and stability of the polystyrene slurries (PSSs), were analyzed, finding an abrupt reduction of the viscosity for PSSs by combining SDS and CS. Addition of SDS and CS (3.0 and 1.5 wt.%, respectively) allowed to produce PSSs with improved stability (ζ = − 48.5 mV after 1 year), low viscosity (20.5 mPa·s at 25 °C), and Newtonian behavior, containing up to 40.0 wt.% of single-spherical PS nanoparticles (< 100 nm). [ABSTRACT FROM AUTHOR]

Recent technological advances enabled modern robots to become part of our daily life. In particular, assistive robotics emerged as an exciting research topic that can provide solutions to improve the quality of life of elderly and vulnerable people. This paper introduces the robotic platform developed in the ENRICHME project, with particular focus on its innovative perception and interaction capabilities. The project's main goal is to enrich the day-to-day experience of elderly people at home with technologies that enable health monitoring, complementary care, and social support. The paper presents several modules created to provide cognitive stimulation services for elderly users with mild cognitive impairments. The ENRICHME robot was tested in three pilot sites around Europe (Poland, Greece, and UK) and proven to be an effective assistant for the elderly at home. [ABSTRACT FROM AUTHOR]

Abstract: An in situ shape-stabilized phase change material (ssPCM) from polyethylene glycol (PEG) has been produced by sol-gel method. The inorganic matrix was in situ formed from tetraethyl orthosilicate (TEOS), controlling the condensation rate in a second alkaline step using NaOH. ssPCMs having a latent heat up to 113.8 J/g were synthetized using a sol with a molar ratio H2O:EtOH:H2SO4:PEG1000:TEOS of 2:0.34:0.021:0.50:1 and an equivalent ratio NaOH/H2SO4 of 1.15 for promoting the gel step. The presence of high-density hydrogen bonds between silanol groups and the ether oxygen atoms of PEG and the existence of latent heat allowed to confirm that the PEG worked in two ways. It either forms the PEG-SiO2 matrix or adsorbs onto the surface of the previous polymeric matrix, losing or conserving its latent heat, respectively. The addition of NaOH allowed to change the functionality of the silicon matrix which strongly affected the water content, the thermal stability, and the amount of active PEG in the ssPCMs, leading to an optimal neutralization condition when an equivalent ratio NaOH/H2SO4 of 1.15 was used. The obtained ssPCM has an appropriate range of operative temperatures, a high latent heat in the range of common thermoregulating materials, and a proper thermal reliability.An in situ shape-stabilized phase change material from polyethylene glycol has been produced by sol-gel method, studying the effect of the condensation step on its final properties. Sol-gel method was used for the in situ production of a ssPCM from PEG and SiO2.The sol condensation rate was controlled by adding NaOH in the neutralization step.PEG works either by forming the PEG-SiO2 matrix or adsorbing onto this solid as PCM.The SiO2 functionality was established by the neutralization degree.The competition between PEG and SiO- by SiOH groups led to obtain an optimal ssPCM. [ABSTRACT FROM AUTHOR]

Renewable resources are playing a key role on the synthesis of biodegradable polyols. Moreover, the incorporation of covalently linked additives is increasing in importance in the polyurethane (PU) market. In this work, previously epoxidized grape seed oil and methyl oleate were transformed into phosphorylated biopolyols through an acid-catalyzed ring-opening hydrolysis in the presence of H3PO4. The formation of phosphate polyesters was confirmed by FT-IR and 31P-NMR. However, the synthesis of a high-quality PU rigid foam was not possible using exclusively these polyols attending to their low hydroxyl value. In that way, different rigid PU foams were prepared from the phosphorylated biopolyols and the commercial polyol Alcupol R4520. It was observed that phosphorylated biopolyols can be incorporated up to a 57 wt.% in the PU synthesis without significant structural changes with respect to the commercial foam. Finally, thermogravimetric and EDAX analyses revealed an improvement of thermal stability by the formation of a protective phosphorocarbonaceous char layer. [ABSTRACT FROM AUTHOR]

The thermal and rheological properties of suspensions of microencapsulated phase change materials (MPCM) in glycerol were investigated. When the microcapsule concentration is raised, the heat storage capacity of the suspensions becomes higher and a slight decline in the thermal conductivity of the suspensions is observed. The temperature-dependent shear-thinning behaviour of the suspensions was found to be strongly affected by non-encapsulated phase change materials (PCM). Accordingly, the rheological properties of the MPCM suspensions could be described by the Cross model below the PCM melting point while a power law model best described the data above the PCM melting point. The MPCM suspensions are interesting for energy storage and heat transfer applications. However, the non-encapsulated PCM contributes to the agglomeration of the microcapsules, which can lead to higher pumping consumption and clogging of piping systems. [ABSTRACT FROM AUTHOR]

A new aromatization method for olive oils with saffron aqueous extracts rich in safranal has been developed using liquid–liquid extraction. Four flavoured olive oils were obtained (SO1–SO4). SO1 showed the highest safranal concentration (145.89 mg L−1), followed by SO2 (79.33 mg L−1), SO3 (0.30 mg L−1) and SO4 (0.01 mg L−1). Although flavouring originated a decrease in the quality parameters and the oxidative stability of the oils, even after 7 months of storage, at room and refrigeration temperatures, the oil parameters evaluated were still comparable to those of extra virgin olive oil. Flavored olive oils with less safranal (SO3, SO4) are preferred by consumers. [ABSTRACT FROM AUTHOR]

The adsorption of polyvinylpyrrolidone (PVP) by the thermoregulating microcapsules has been studied. The mass ratio of PVP has been changed from 1 to 20, with respect to the lowest amount of PVP value (4.08 g). The results confirmed that a large amount of PVP was adsorbed by the polymeric shell. Experimental data were perfectly fitted by Langmuir model, obtaining at a confidence level of 95% values of 192.9 ± 0.4 g/kg and 0.18 ± 0.11 m/kg for the maximum adsorption capacity and the equilibrium constant, respectively. It was found that utilizing PVP, at a concentration of 5.03 wt% of the total mass provided optimum conditions for synthesizing thermoregulating microcapsules containing Rubitherm®RT27 from poly(styrene-divinylbenzene) (P(St-DVB)), with the best thermal and physical properties. Finally, the robustness of the process was checked at a large scale by using a reactor that maintains geometrical similarities with that used at laboratory scale. The thermal properties, the encapsulation efficiency, and the microcapsule yield were similar, but at pilot plant scale, narrower particle size distributions were obtained. [ABSTRACT FROM AUTHOR]

Therapies that target the programmed death-1 (PD-1) receptor have shown unprecedented rates of durable clinical responses in patients with various cancer types. One mechanism by which cancer tissues limit the host immune response is via upregulation of PD-1 ligand (PD-L1) and its ligation to PD-1 on antigen-specific CD8+ T cells (termed adaptive immune resistance). Here we show that pre-existing CD8+ T cells distinctly located at the invasive tumour margin are associated with expression of the PD-1/PD-L1 immune inhibitory axis and may predict response to therapy. We analysed samples from 46 patients with metastatic melanoma obtained before and during anti-PD-1 therapy (pembrolizumab) using quantitative immunohistochemistry, quantitative multiplex immunofluorescence, and next-generation sequencing for T-cell antigen receptors (TCRs). In serially sampled tumours, patients responding to treatment showed proliferation of intratumoral CD8+ T cells that directly correlated with radiographic reduction in tumour size. Pre-treatment samples obtained from responding patients showed higher numbers of CD8-, PD-1- and PD-L1-expressing cells at the invasive tumour margin and inside tumours, with close proximity between PD-1 and PD-L1, and a more clonal TCR repertoire. Using multivariate analysis, we established a predictive model based on CD8 expression at the invasive margin and validated the model in an independent cohort of 15 patients. Our findings indicate that tumour regression after therapeutic PD-1 blockade requires pre-existing CD8+ T cells that are negatively regulated by PD-1/PD-L1-mediated adaptive immune resistance. [ABSTRACT FROM AUTHOR]

Growth of undesirable moulds is one of the major causes of defects in modern cheese production, and it is necessary to discover natural antifungal substances that are non-toxic to humans. Saffron spice has been successfully used as a new ingredient in some Italian or Spanish cheeses, but transference of safranal (the main compound responsible for saffron aroma) during cheesemaking has not yet been studied. In this study, the distribution of safranal in cheese, whey and requesón (Spanish whey cheese) and the antifungal potential of whey fractions against the mould Penicillium verrucosum were studied. To this end, a duplicate fabrication of cheeses was performed with raw ewe's milk with the addition of 40 μg safranal.kg −1 or control milk (no safranal addition). Safranal was more concentrated in cheese and requesón (78.91 and 76.95 μg.kg −1, respectively) than in whey and requesón whey (35.19 and 34.64 μg.kg −1, respectively). These liquid fractions showed good antifungal properties and inhibited mould with a safranal concentration of around 35 μg.kg −1, while a solution of 80 μg.kg −1 was required for a standard safranal solution to obtain a similar inhibition. These results reveal that whey has a synergistic effect with safranal in preventing cheese spoilage by moulds, which encourages making full use of this problematic by-product. [ABSTRACT FROM AUTHOR]

A highly selective method was developed for the simultaneous determination of eight penicillins in catfish using automated on-line solid-phase extraction coupled to liquid chromatography-tandem mass spectrometry (XLC-MS/MS). The type of cartridge, equilibration sample volume, volume of solvent to carry the sample into the cartridge, and elution times were studied in order to optimize the XLC operating conditions. MS/MS conditions were also adjusted for better peak resolution. The present method was validated in agreement with the criteria of Commission Decision 2002/657/EC, showing a linear range from 2 to 350 μg kg and regression coefficient higher than 0.995 for the studied penicillins. Decision limits, calculated in the case of substances with no permitted limit, were lower than 0.6 μg kg, and detection capability values were lower than 2.0 μg kg. Samples spiked at 2.0, 10.0, and 50.0 μg kg showed high recovery (72-92%) and precision values lower than 20% except for amoxicillin. The present method was also applied for the analysis of penicillins in 30 catfish samples bought in local markets. [ABSTRACT FROM AUTHOR]

Catalyst Tegoamin 33 has been used for the synthesis of rigid polyurethane (RPU) foams containing microencapsulated Rubitherm RT27 and having a high mechanical resistance. These materials could be employed in buildings for thermal insulation and thermal energy storage (TES). The fillers content influence on the foaming process and also the foam properties was evaluated. It was observed that a foam containing up to a 18 wt% of microcapsules can be manufactured, improving the TES capacity while maintaining the mechanical properties of the neat foam. Besides, it was observed that the mechanical resistance of foams synthesized using catalyst Tegoamin 33 are higher than those obtained when catalyst Tegoamin BDE was employed, with the mechanical resistance of the foam containing 21 wt% being higher than those of foams synthesized with catalyst BDE containing only 11 wt% of fillers while maintaining the advantages of an improvement in TES capacity. A general model of reaction curve of n tank-in-series of a same time constant was used to fit the rising curves. This model allowed to predict the final volume of the synthesized foam. Finally, TES capacities and mechanical properties of the synthesized foams were in the range of those reported in literature. Moreover, foam densities satisfied the restriction established by the Spanish regulation for building applications. [ABSTRACT FROM AUTHOR]

Rigid polyurethane foams (RPU foams) and phase change materials (PCMs) are widely used in buildings for thermal insulation and thermal storage, respectively. The combination of both materials could increase energy savings, leading to more energy efficient housing. In this work, PU foams were produced incorporating different percentages of microcapsules containing Rubitherm® RT27. Microcapsules added to the foam had a high influence on the foaming process and also on the foam properties. It was observed that the increase of foam microcapsules content decreases the final foam height but increases its density and thermal energy storage (TES) capacity. On the other hand, an increase of the foam microcapsules content up to 5 wt% led to decrease the reduced compressive strength (RS) and modulus (RE) in 7 and 25%, respectively. Higher contents had a sharply negative impact on mechanical properties. [ABSTRACT FROM AUTHOR]

Thin-film exchangers have a large heat-transfer area per unit liquid volume that make them very efficient for industrial use. Unfortunately, they are usually less applied for education purposes. In this work, a simple experimental device with a fluid flowing as a falling film has been assembled. In addition, an experimental guide allows students to determine the individual heat-transfer coefficient in the exchanger. The experimental setup consists of two pipes bundled as a shell-and-tube heat exchanger. The cold liquid flows in the form of a thin film that runs down inside the inner tube; the hot liquid flows down concurrently in the external one. In order to test the operation of the device, experimental results are given for a simple test with water. Heat-transfer coefficients are calculated and a theoretical correlation obtained from the literature is compared with the experimental results. In addition, a fit of the data allows for the formulation of a new empirical equation for the transient regime. [ABSTRACT FROM AUTHOR]

A stopped-flow method for the determination of paracetamol and oxyphenbutazone individually and in mixtures with no prior separation is proposed. The method is based on the oxidation of these drugs by the tris(2,2′-bipyridine)-iron(III) complex in an acid medium. The reactions are monitored by measuring the rate of appearance of the absorbance of the ferroin complex ( λ=490 nm). The calibration graphs for the individual determination of the two drugs are both linear in the range 5-40 μg ml, and the precision (R.S.D.) is about 2%. A linear graphical differential reaction rate method is used for the resolution of mixtures of these drugs at the μg ml level at paracetamol/ oxyphenbutazone ratios from 6∶1 to 1∶2. The proposed method is practically free from interferences. [ABSTRACT FROM AUTHOR]