Particles adsorbed at liquid interfaces are commonly used to stabilise water-oil Pickering emulsions and water-air foams. The fundamental understanding of the physics of particles adsorbed at ...water-air and water-oil interfaces is improving significantly due to novel techniques that enable the measurement of the contact angle of individual particles at a given interface. The case of non-aqueous interfaces and emulsions is less studied in the literature. Non-aqueous liquid-liquid interfaces in which water is replaced by other polar solvents have properties similar to those of water-oil interfaces. Nanocomposites of non-aqueous immiscible polymer blends containing inorganic particles at the interface are of great interest industrially and consequently more work has been devoted to them. By contrast, the behaviour of particles adsorbed at oil-oil interfaces in which both oils are immiscible and of low dielectric constant (ε<3) is scarcely studied. Hydrophobic particles are required to stabilise these oil-oil emulsions due to their irreversible adsorption, high interfacial activity and elastic shell behaviour.
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•We compile the major results about particle-laden oil-oil interfaces.•The oil/oil polymer bijels can be stabilised by hydrophobic inorganic particles.•Oil-oil interfaces of ε<3 can be stabilised by hydrophobic particles.
The impact resistance of injection‐molded polypropylene (PP) parts is severely reduced when they are foamed. It is necessary to implement strategies, such as elastomer toughening, to increase the ...impact behavior of foamed parts. However, the knowledge on the effect of elastomer addition on the morphology, cellular structure, and impact of injection‐molded cellular parts is very limited. In this work, foamed parts based on blends of PP and polyolefin elastomers have been produced and characterized. A high and a low viscosity octene‐ethylene copolymer (EOC) and a high viscosity butene‐ethylene copolymer (EBC) were employed. The blends have been thermally and rheological characterized. Solids materials and foams (relative density 0.76) were injection‐molded. The solid phase and cellular structure morphologies were studied using scanning electron microscopy. The results showed that elastomer toughening has been successful to obtain an improvement of the impact behavior in solid and cellular polymers. In this case, EOC materials provide an appropriate interfacial adhesion and optimized cellular structure which results in high impact resistance. The optimum elastomer to improve the properties is the EOC with a higher viscosity which provides impact resistance with n values below 3 due to the toughening of polymer matrix, thick skin thickness, and low cell size.
Polyolefin elastomers with different viscosities and composition has been blended with PP, producing solids and foamed materials by injection molding. The rheological properties of the elastomers and blend are crucial in the observed cellular and dispersed phase structures, and in the final impact performance. The viscosity of the elastomer seems to be more important than the elastomer morphology or the interfacial adhesion in the final properties of the foamed and solids materials.
The ageing process is highly heterogeneous leading to diverse ageing trajectories. Such trajectories have been modelled to study trends and determinants of ageing and could potentially be used to ...inform the planning of rehabilitation services at population level. The objective of this paper was to explore whether healthy ageing trajectories are suitable to identify targets for rehabilitation interventions for the ageing population. Data from the Ageing Trajectories of Health: Longitudinal Opportunities and Synergies (ATHLOS) harmonized cohort and the English Longitudinal Study of Ageing (ELSA), which is included in ATHLOS, were used. Growth mixture models were implemented to replicate healthy ageing trajectories modelled elsewhere as 'high stable', 'low stable', and 'rapid decline'. Regularized partial correlation networks were used to estimate expected-influence and bridge expected-influence centrality measures. Healthy ageing trajectories modelled with ATHLOS (N = 131116) and ELSA (N = 14904) were consistent with previous work. At the first individual wave, prevalence of problems of respondents in the 'high stable' and 'rapid decline' trajectories were comparable; at the last individual wave, prevalence remained similar for the 'high stable' but increased substantially in all domains for the 'rapid decline' trajectory. Expected-influence centrality measures provided different results than prevalence estimates. For instance, in the first individual wave mobility and carrying, moving, and handling objects had highest impact on overall functioning for the 'rapid decline' and 'high stable' trajectories, while the most prevalent functioning problems concerned cognition, pain, as well as energy and drive functions. Our study stressed the relevance of healthy ageing trajectories for identifying functioning domains and categories that need to be targeted by rehabilitation services in a heterogeneous ageing population. The use of such trajectories at country level has the potential to make a meaningful contribution to the planning and delivery of rehabilitation interventions through health systems and to informed policy making.
Pressurized water reactors are designed to operate in a single-phase flow. However, during a flow loss or other off-design conditions liquid temperature may exceed saturation temperature and, if a ...continuous film of gas forms, a boiling casualty may result. If superhydrophobic surfaces are introduced among the fuel cell assembly, vapor bubbles show an affinity to these surfaces and gas may coalesce to escape faster, resulting in a larger margin to reach critical heat flux. In the present study, we consider air and liquid water mixture examining the overall flow dynamics in a case with no bulk liquid flow, reminiscent of a case with coolant pump failure. The parameter ranges examined span Reynolds number based on gas superficial velocity up to 5300 and produced bubble with bond numbers from 1 to 270, and Weber numbers based on estimated terminal velocity from 0.6 to 150. The Morton number was fixed at
2.63
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11
. As the flow with high gas volume fraction becomes optically opaque and is sensitive to intrusive instrumentation, a custom-built photon-counting dual energy threshold X-ray computed tomography system is employed for measurement of the time average void fraction within the bundle non-intrusively. Two dual plane wire mesh sensors upstream and downstream of the rod bundle are employed to obtain comparison void fraction, velocity profiles and bubble size distributions. Additionally, traditional pressure-based gas holdup measurements are employed to calculate time- and volume-averaged void fraction. The data show that the presence of superhydrophobic surface being present in the rod bundle results in a significantly lower gas volume fraction and higher localized void fraction at the superhydrophobic coating, as compared to those in a similar rod bundle without superhydrophobic internals.
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Surface heterogeneity affects the behavior of nanoparticles at liquid interfaces. To gain a deeper understanding on the details of these phenomena, we have measured the interfacial activity and ...contact angle at water/decane interfaces for three different types of nanoparticles: homogeneous poly(methyl methacrylate) (PMMA), silica functionalized with a capping ligand containing a methacrylate terminal group, and Ag-based Janus colloids with two capping ligands of different hydrophobicity. The interfacial activity was analyzed by pendant drop tensiometry, and the contact angle was measured directly by freeze-fracture shadow-casting cryo-scanning electron microscopy. The silver Janus nanoparticles presented the highest interfacial activity, compared to the silica nanoparticles and the homogeneous PMMA nanoparticles. Additionally, increasing the bulk concentration of the PMMA and silica nanoparticles up to 100-fold compared to the Janus nanoparticles led to silica particles forming fractal-like structures at the interface, contrary to the PMMA particles that did not show any spontaneous adsorption.
The study of the viability of hydrogen production as a sustainable energy source is a current challenge, to satisfy the great world energy demand. There are several techniques to produce hydrogen, ...either mature or under development. The election of the hydrogen production method will have a high impact on practical sustainability of the hydrogen economy. An important profile for the viability of a process is the calculation of energy and exergy efficiencies, as well as their overall integration into the circular economy. To carry out theoretical energy and exergy analyses we have estimated proposed hydrogen production using different software (DWSIM and MATLAB) and reference conditions. The analysis consolidates methane reforming or auto-thermal reforming as the viable technologies at the present state of the art, with reasonable energy and exergy efficiencies, but pending on the impact of environmental constraints as CO
emission countermeasures. However, natural gas or electrolysis show very promising results, and should be advanced in their technological and maturity scaling. Electrolysis shows a very good exergy efficiency due to the fact that electricity itself is a high exergy source. Pyrolysis exergy loses are mostly in the form of solid carbon material, which has a very high integration potential into the hydrogen economy.
Worldwide, Mycoplasma gallisepticum (MG) and M. synoviae (MS) are the main agents responsible for chronic respiratory disease in poultry. Therefore, we conducted a systematic review and meta‐analysis ...to estimate their occurrence. We searched electronic databases to find peer‐reviewed publications reporting the molecular detection of MG and MS in poultry and used meta‐analysis to estimate their pooled global occurrence (combined flock and individual), aggregating results at the regional and national levels. We performed a subgroup meta‐analysis for subpopulations (broilers, layers, breeders and diverse poultry including turkeys, ducks and ostriches) and used meta‐regression with categorical modifiers. We retrieved 2294 publications from six electronic databases and included 85 publications from 33 countries that reported 62 studies with 22,162 samples for MG and 48 studies with 26,413 samples for MS. The pooled global occurrence was 38.4% (95% CI: 23.5–54.5) for MS and 27.0% (20.4–34.2) for MG. Among regions, Europe and Central Asia had the lowest occurrence for both pathogens, while MG and MS were highly prevalent in South Asia and sub‐Saharan Africa, respectively. At the national level, MG occurrence was higher in Algeria, Saudi Arabia and Sudan, whereas China, Egypt and Ethiopia reported higher values of MS. Among the poultry subpopulations, MS and MG were more prevalent in the breeders and layers (62.6% and 31.2%, respectively) than in diverse poultry. The year of publication, the sample size and the level of ambient air pollution (measured indirectly by PM2.5) were associated with the occurrence of both mycoplasmas. Our study revealed high and heterogeneous occurrence values of MG and MS and justifies the need for early detection and improved control measures to reduce the spread of these pathogens.
We previously reported the eradication of human epidermal growth factor receptor 2 (HER2)- amplified human xenografts in mice by inhibition of the HER2 pathway with lapatinib and trastuzumab to block ...all homo- and heterodimer signaling as well as by blockade of estrogen receptor (ER) when expressed. In this clinical trial, we sought to translate these findings to patients using targeted therapy without chemotherapy.
Women with stages II to III HER2-positive breast cancers were eligible. They received trastuzumab once per week (4 mg/kg loading, then 2 mg/kg) and lapatinib 1000 mg once per day for 12 weeks. Women with ER-positive tumors also received letrozole (plus a luteinizing hormone-releasing hormone LHRH agonist if premenopausal). Pathologic response was assessed by ER status. Biopsies were obtained at baseline, weeks 2 and 8, and time of surgery.
Sixty-six patients were enrolled, and 64 were eligible and evaluable for response. Median tumor size was 6 cm (range, 1.5 to 30 cm). Adverse events were mainly grades 1 to 2 (GI, 63%; skin, 46%). Grade 3 metabolic, GI, and liver (18%; 12 patients) and grade 4 liver toxicities (one patient) were also observed. Overall, in-breast pathologic complete response (pCR; ypT0-is) was 27% (ER positive, 21%; ER negative, 36%). The rate of low-volume residual disease (ypT1a-b) was 22% (ER positive, 33%; ER negative, 4%).
In patients with locally advanced HER2-positive breast cancer, our approach of targeted therapy only resulted in a high pCR rate without chemotherapy. Our data support the hypothesis that selected patients with HER2-positive tumors may not need chemotherapy, and more-complete blockade of HER receptors and ER is an effective strategy worthy of further study.
The interfacial activity of 3.5 nm homogeneous (HPs) and amphiphilic Janus gold nanoparticles (JPs) was characterized by pendant drop tensiometry for water/air and water/decane interfaces. This ...technique requires a smaller quantity of nanoparticles than the traditional Langmuir balance technique. The direct deposition at the interface of the nanoparticles dispersed in a spreading solvent also requires smaller quantities of sample than does adsorption from the bulk. From the growing and shrinking of the pendant drops, the interfacial activity of the nanoparticles can be evaluated and compared within a wide range of area per particle. In this work, the JPs exhibited a higher interfacial activity than did the HPs in all cases. A hard disk model fits the piecewise compression isotherm of the HPs, yet this model underestimates the interactions between the JPs adsorbed at the interface.
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