Experimental High-Resolution Observation of the Truncated Double-Icosahedron Structure: A Stable Twinned Shell in Alloyed Au-Ag Core@Shell Nanoparticles.

Given the binary nature of nanoalloy systems, their properties are dependent on their size, shape, structure, composition, and chemical ordering. When energy and entropic factors for shapes and structure variations are considered in nanoparticle growth, the spectra of shapes become so vast that even metastable arrangements have been reported under ambient conditions. Experimental and theoretical variations of multiply twinned particles have been observed, from the Ino and Marks decahedra to polyicosahedra and polydecahedra with comparable energetic stability among them. Herein, we report the experimental production of a stable doubly truncated double-icosahedron structure (TdIh) in Au-Ag nanoparticles, in which a twinned Ag-rich alloyed shell is reconstructed on a Au-Ag alloyed Ino-decahedral core. The structure, chemical composition, and growth pathway are proposed on the basis of high-angle annular dark-field scanning transmission electron microscopy analysis and excess energy calculations, while its structural stability is estimated by large-scale atomic molecular dynamics simulations. This novel nanostructure differs from other structures previously reported.

Using Recycled Tetrapak and Doped Titanyl/Vanadyl Phthalocyanine to Make Solid-State Devices.

In this work we studied the semiconductor behavior of titanyl phthalocyanine (TiOPc) and vanadyl phthalocyanine (VOPc), doped with anthraflavic acid and deposited on Tetrapak/graphite as flexible electrodes. The molecular structure was approached using the density functional theory and astonishingly, it was found that the structure and electronic behavior can change depending on the metal in the phthalocyanine. Experimentally, the Root Mean Square was found to be 124 and 151 nm for the VOPc-Anthraflavine and TiOPc-Anthraflavine films, respectively, and the maximum stress was 8.58 MPa for the film with VOPc. The TiOPc-Anthraflavine film presents the smallest fundamental gap of 1.81 eV and 1.98 eV for indirect and direct transitions, respectively. Finally, the solid-state devices were fabricated, and the electrical properties were examined. The tests showed that the current-voltage curves of the devices on Tetrapak and VOPc-Anthraflavine on a rigid substrate exhibit the same current saturation behavior at 10 mA, which is achieved for different voltage values. Since the current-voltage curves of the TiOPc-Anthraflavine on a rigid substrate presents a defined diode model behavior, it was approximated by nonlinear least squares, and it has been determined that the threshold voltage of the sample for the different lighting conditions is between 0.6 and 0.8 volts.

Induced Systemic Resistance in the Bacillus spp.-Capsicum chinense Jacq.-PepGMV Interaction, Elicited by Defense-Related Gene Expression.

Induced systemic resistance (ISR) is a mechanism involved in the plant defense response against pathogens. Certain members of the Bacillus genus are able to promote the ISR by maintaining a healthy photosynthetic apparatus, which prepares the plant for future stress situations. The goal of the present study was to analyze the effect of the inoculation of Bacillus on the expression of genes involved in plant responses to pathogens, as a part of the ISR, during the interaction of Capsicum chinense infected with PepGMV. The effects of the inoculation of the Bacillus strains in pepper plants infected with PepGMV were evaluated by observing the accumulation of viral DNA and the visible symptoms of pepper plants during a time-course experiment in greenhouse and in in vitro experiments. The relative expression of the defense genes CcNPR1, CcPR10, and CcCOI1 were also evaluated. The results showed that the plants inoculated with Bacillus subtilis K47, Bacillus cereus K46, and Bacillus sp. M9 had a reduction in the PepGMV viral titer, and the symptoms in these plants were less severe compared to the plants infected with PepGMV and non-inoculated with Bacillus. Additionally, an increase in the transcript levels of CcNPR1, CcPR10, and CcCOI1 was observed in plants inoculated with Bacillus strains. Our results suggest that the inoculation of Bacillus strains interferes with the viral replication, through the increase in the transcription of pathogenesis-related genes, which is reflected in a lowered plant symptomatology and an improved yield in the greenhouse, regardless of PepGMV infection status.

PDDA induced step-pyramidal growth of nickel-platinum (Ni-Pt) nanoparticles for enhanced 4-nitrophenol reduction.

Herein, we report the synthesis of novel platinum-based nanoparticles with step-pyramidal growth induced by poly(diallyldimethylammonium chloride) (PDDA). The complex stepped pyramidal shape became the central point for outstanding catalytic reduction of 4-nitrophenol, overcoming the activity of bare Pt nanoparticles. These results are valuable for the catalytic degradation of reactive molecules.

Spiers Memorial Lecture: Nanoalloys of multiple components; the road to advance the field and experimental and theoretical challenges.

The field of nanoalloys has been advancing at a rapid pace in the last two decades. Many new characterization methods and theoretical advances have produced a substantial knowledge of the nanoalloys' properties and structure. Most of the work has been limited to binary alloys. A path forward for the field will be the study of nanoalloys with three or more metals. Adding new components will produce new properties and possibly more fabrication controls. In this paper, we will discuss the challenges that will arise in multi-metallic nanoalloys. We will show that entropy and twin boundaries play a dominant role in multi-metallic alloys.

Factores cardiometabólicos asociados y prevalencia de concentraciones bajas de colesterol HDL y de dislipidemia aterogénica. Estudio SIMETAP-DA / Related cardiometabolic factors and prevalence of low HDL-cholesterol levels and atherogenic dyslipidemia. SIMETAP-AD study

OBJETIVO: Determinar las prevalencias ajustadas por edad y sexo de concentraciones bajas de colesterol HDL (cHDL-bajo) y de dislipidemia aterogénica (DA), y valorar sus asociaciones con factores de riesgo cardiovascular, enfermedad renal crónica, enfermedades cardiovasculares y cardiometabólicas. MÉTODOS: Estudio observacional transversal de base poblacional realizado en atención primaria, con sujetos adultos seleccionados aleatoriamente. Se consideró DA si los pacientes tenían hipertrigliceridemia (triglicéridos≥150mg/dL) y cHDL-bajo (<40mg/dL [hombres],<50mg/dL [mujeres]). Se determinaron las tasas de prevalencia crudas y ajustadas por edad y sexo, y se realizó análisis univariado y multivariante para evaluar los factores cardiometabólicos relacionados. RESULTADOS: Población de estudio con 6.588 adultos (55,9% mujeres) con edad media de 55,1 (±17,5) años. Las medias de cHDL fueron 49,2 (±12,6) mg/dL en hombres y 59,2 (±14,7) mg/dL en mujeres. Las prevalencias crudas de cHDL-bajo y de DA fueron 30,8% (IC95%: 29,7-31,9), y 14,3% (IC95%: 13,5-15,2), respectivamente. Las prevalencias ajustadas de cHDL-bajo fueron 28% en hombres y 31% en mujeres, y de DA fueron 16,4% en hombres y 10,6% en mujeres. El 73% de la población con DA tenía riesgo cardiovascular alto o muy alto. Los factores independientes asociados con cHDL-bajo o con DA fueron diabetes, tabaquismo, obesidad abdominal y obesidad. Los principales factores asociados con cHDL-bajo y con DA fueron hipertrigliceridemia y diabetes, respectivamente. CONCLUSIONES: Casi un tercio de la población adulta presentaba cHDL-bajo y la mitad de ellos cumplía criterios de DA. Los factores cardiometabólicos se asociaban con cHDL-bajo y DA, destacando la hipertrigliceridemia con el cHDL-bajo, y la DM con la DA

AIM: To determine the crude and sex- and age-adjusted prevalence rates of atherogenic dyslipidemia (AD) and low HDL-cholesterol levels (low-HDLc), and to assess their associations with cardiovascular risk factors, chronic kidney disease, cardiovascular and cardiometabolic diseases. METHODS: Population-based cross-sectional study conducted in Primary Care, with randomly selected adult subjects. The AD was considered if the patients had hypertriglyceridemia (triglycerides≥150mg/dL) and low-HDLc (<40mg/dL [men];<50mg/dL [women]). Crude and sex- and age-adjusted prevalence rates were determined, and univariate and multivariate analysis were performed to assess related cardiometabolic factors. RESULTS: Study population with 6,588 adults (55.9% women) with mean age 55.1 (±17.5) years. The mean HDLc levels were 49.2 (±12.6) mg/dL in men and 59.2 (±14.7) mg/dL in women. The crude prevalence rates of low-HDLc and AD were 30.8% (95%CI: 29.7-31.9), and 14.3% (95%CI: 13.5-15.2), respectively. The adjusted prevalence rates of low-HDLc were 28.0% in men and 31.0% in women, and AD were 16.4% in men and 10.6% in women. Seventy-three percent of the population with AD had high or very high cardiovascular risk. The independent factors associated with low HDLc or with AD were diabetes, smoking, abdominal obesity, and obesity. The major factors associated with low HDLc and AD were hypertriglyceridemia and diabetes, respectively. CONCLUSIONS: Almost a third of the adult population had low HDL-C and half of them met AD criteria. Cardiometabolic factors were associated with low HDL-C and AD, highlighting hypertriglyceridemia with low HDLc, and DM with AD

Related cardiometabolic factors and prevalence of low HDL-cholesterol levels and atherogenic dyslipidemia. SIMETAP-AD study. / Factores cardiometabólicos asociados y prevalencia de concentraciones bajas de colesterol HDL y de dislipidemia aterogénica. Estudio SIMETAP-DA.

AIM: To determine the crude and sex- and age-adjusted prevalence rates of atherogenic dyslipidemia (AD) and low HDL-cholesterol levels (low-HDLc), and to assess their associations with cardiovascular risk factors, chronic kidney disease, cardiovascular and cardiometabolic diseases. METHODS: Population-based cross-sectional study conducted in Primary Care, with randomly selected adult subjects. The AD was considered if the patients had hypertriglyceridemia (triglycerides≥150mg/dL) and low-HDLc (<40mg/dL [men];<50mg/dL [women]). Crude and sex- and age-adjusted prevalence rates were determined, and univariate and multivariate analysis were performed to assess related cardiometabolic factors. RESULTS: Study population with 6,588 adults (55.9% women) with mean age 55.1 (±17.5) years. The mean HDLc levels were 49.2 (±12.6) mg/dL in men and 59.2 (±14.7) mg/dL in women. The crude prevalence rates of low-HDLc and AD were 30.8% (95%CI: 29.7-31.9), and 14.3% (95%CI: 13.5-15.2), respectively. The adjusted prevalence rates of low-HDLc were 28.0% in men and 31.0% in women, and AD were 16.4% in men and 10.6% in women. Seventy-three percent of the population with AD had high or very high cardiovascular risk. The independent factors associated with low HDLc or with AD were diabetes, smoking, abdominal obesity, and obesity. The major factors associated with low HDLc and AD were hypertriglyceridemia and diabetes, respectively. CONCLUSIONS: Almost a third of the adult population had low HDL-C and half of them met AD criteria. Cardiometabolic factors were associated with low HDL-C and AD, highlighting hypertriglyceridemia with low HDLc, and DM with AD.

Cuando la memoria se hace opaca y solo el dolor fulgura: abordaje sanitario del fenómeno suicida en Las vírgenes suicidas (1999) de Sofia Coppola / When memories become opaque and only the pain glows: Sanitary approach of the suicidal phenomenon in The Virgin Suicides (1999) by Sofia Coppola

En la década de 1970, en una ciudad norteamericana, cinco hermanas entre los trece y los diecisiete años cometieron suicidio, comenzado por Cecilia, la menor de las hermanas Lisbon. Una ola de tristeza plagada de interrogantes inundó las mentes de aquellos que convivieron con ellas y de todos aquellos fueron testigos de cómo poco a poco fueron perdiendo su alegría, sus motivaciones y su esencia hasta convertirse en sombras inexpresivas de lo que una vez fueron. Ante las peculiaridades descritas entre las muertes de las hermanas en las Vírgenes suicidas de Sofía Coppola 1999, el espectador puede plantearse diversas cuestiones relacionadas con el manejo sanitario adecuado y el papel del personal de salud para abordar de manera óptima la salud mental durante la adolescencia y de las medidas de prevención recomendables tanto en lo individual como en lo colectivo. El presente artículo se ofrece como un análisis a propósito de las conductas suicidas ficticias reportadas en el filme, como si de algún modo, las hermanas Lisbon pudiesen atenderse con los recursos y conocimientos que tienen en la actualidad los médicos contemporáneos a través

In the 1970s, in the suburbs of a US city, five sisters between thirteen and seventeen years of age committed suicide, starting with Cecilia, the youngest of the Lisbon sisters. A wave of sadness plagued with questions invaded the minds of those who lived with them and of all those who witnessed how little by little they lost their joy, their motivations and their essence until they became inexpressive shadows of what they once were. Given the peculiarities described between the deaths of the sisters in the Suicide Virgins of Sofia Coppola 1999, the expectation may ask several questions related to proper health approach and the role of health personnel to optimally address mental health in adolescence and of preventive measures recommended in both, individual and collective levels. This article is offered as an analysis of the fictional suicidal behaviors reported in the film, as if in some way, the Lisbon sisters could be treated with the resources and knowledge that contemporary doctors have in present time through the healthcare system, without ignoring the conditions in which their tragic deaths occurred

Analysis of Fall Risk Factors in an Aging Population Living in Long-Term Care Institutions in SPAIN: A Retrospective Cohort Study.

Falls in the elderly are associated with morbidity and mortality. Research about fall risk factors in Spanish care facilities is scarce. This study aimed to assess the prevalence of falls among residents living in long-term care Spanish institutions and to identify fall risk factors in this population. A nationwide retrospective cohort study was conducted in 113 centers. Persons over 70 years old who were living in a residential setting for at least 1 year were included. Simple and multiple regression analyses were conducted to estimate the associations between the main clinical variables registered in the databases and the presence of falls. A total of 2849 subjects were analyzed (mean age 85.21 years). The period prevalence of fallers in the last 12 months was 45.3%, with a proportion of recurrent fallers of 51.7%. The presence of falls was associated with lower Tinetti Scale scores (OR = 1.597, 95% CI: 1.280, 1.991; OR = 1.362, 95% CI: 1.134, 1.635), severe or moderate cognitive impairment (OR= 1.992, 95% CI: 1.472, 2.695; OR = 1.507, 95% CI: 1.231, 1.845, respectively), and polypharmacy (OR = 1.291, 95% CI: 1.039, 1.604). Fall prevention interventions should focus on the prevention of balance and cognitive deterioration and the improvement of these functions when possible. It should also focus on a periodical medication history revision aiming to avoid inappropriate prescriptions.

Gold Nanoclusters, Gold Nanoparticles, and Analytical Techniques for Their Characterization.

Many reliable and reproducible methods exist for manufacturing gold nanoparticles with the desired and specific compositions, structures, arrangements, and physicochemical properties. In this report, we review the key principles guiding the formation and growth of nanoclusters, their evolution into nanoparticles, and the role and contribution of coatings. We describe a range of imaging methods for characterization of nanoparticles at atomic resolution and a range of spectroscopy methods for structural and physicochemical characterization of such nanoparticles. This chapter concludes with a short review of the emergent applications of nanoparticles in biosciences.

Controlled Overgrowth of Five-Fold Concave Nanoparticles into Plasmonic Nanostars and Their Single-Particle Scattering Properties.

Growth of anisotropic nanostructures enables the manipulation of optical properties across the electromagnetic spectrum by fine morphological tuning of the nanoparticles. Among them, stellated metallic nanostructures present enhanced properties owing to their complex shape, and hence, the control over the final morphology becomes of great importance. Herein, a seed-mediated method for the high-yield production of goldrich-copper concave branched nanostructures and their structural and optical characterization is reported. The synthesis protocol enabled excellent control and tunability of the final morphology, from concave pentagonal nanoparticles to five-fold branched nanoparticles, named "nanostars". The anisotropic shape was achieved via kinetic control over the synthesis conditions by selective passivation of facets using a capping agent and assisted by the presence of copper chloride ions, both having a crucial impact over the final structure. Optical extinction measurements of nanostars in solution indicated a broad spectral response, hiding the properties of the individual nanostars. Hence, single-particle scattering measurements of individual concave pentagonal nanoparticles and concave nanostars were performed to determine the origin of the multiple plasmon bands by correlation with their morphological features, following their growth evolution. Finite-difference time-domain calculations delivered insights into the geometry-dependent plasmonic properties of concave nanostars and their packed aggregates. Our results uncover the intrinsic scattering properties of individual nanostars and the origin of the broad spectral response, which is mostly due to z-direction packed aggregates.

Regeneración de árboles en ecosistemas naturales y plantaciones de Pinus patula (Pinaceae) dentro de un gradiente altitudinal andino (Azuay, Ecuador) / Regeneration of trees in natural ecosystems and plantations of Pinus patula (Pinaceae), in an Andean altitudinal gradient (Azuay, Ecuador)

Resumen Los bosques y páramos andinos poseen alta riqueza de especies, pero están amenazados constantemente por deforestación. La regeneración natural arbórea de estos ecosistemas condiciona su estructura y funcionalidad en el futuro, pero ha sido escasamente evaluada. En Los Andes del sur del Ecuador, también existen plantaciones forestales de Pinus patula (pino) abandonadas, que podrían ser escenarios para promover la regeneración natural. En un gradiente altitudinal andino, se evaluó florísticamente parámetros de la regeneración arbórea en dos escenarios de estudio: ecosistemas naturales (páramos herbáceos y bosques naturales) y plantaciones de pino. Para ello la diversidad de la regeneración fue descrita mediante la riqueza de especies, índice de Shannon y composición florística. La abundancia a través del número de individuos; estos parámetros fueron comparados en ambos escenarios. También se determinó qué variables ambientales o predictoras de: cobertura de dosel, edáficas, estructura arbórea, distancia horizontal y fisiográficas, explicaron con mayor magnitud la variación en los parámetros de la regeneración. Para ello se realizó un análisis de partición de la variación. La riqueza y diversidad de especies fueron mayores en los ecosistemas naturales, la composición florística fue diferente y su abundancia fue similar. En los ecosistemas naturales, el área basal y la densidad arbórea explicaron mayormente la variación en la riqueza, diversidad y abundancia. No así en las plantaciones de pino en donde la distancia horizontal hacia los bosques nativos fue la predictora que mayormente las explicó. La mayor diversidad de regeneración en los ecosistemas naturales (bosques) está asociada con la existencia de biotipos arbóreos, arbustivos y disponibilidad de semillas, adicionando a la eficiencia en los procesos de dispersión a nivel de micro-hábitat, aspectos que son limitantes en las plantaciones de pino, en los cuales la dispersión o disponibilidad de semillas depende de la cercanía a los ecosistemas naturales.

Abstract Andean forests and paramo have high species richness, but constantly they are threatened by deforestation. Natural arboreal regeneration of these ecosystems will condition their structure and functionality in the future, but now it has been poorly evaluated. In the Andes of Southern Ecuador, there are also abandoned Pinus patula (pine) forest plantations, which could be scenarios to promote natural regeneration. In an Andean altitudinal gradient, we evaluated floristically parameters of tree regeneration between two study scenarios: natural ecosystems (herbaceous paramos and natural forests) and pine plantations. For this, the diversity of regeneration was described by species richness, Shannon index and floristic composition. Abundance with the number of individuals; these parameters were compared between two scenarios. We determined also that environmental variables or predictors of: canopy cover, soil, tree structure, horizontal distance and physiographic explained the variation in the parameters of regeneration with greater magnitude. For this, a partition analysis of the variation was carried out. Richness and diversity of species were greater in natural ecosystems, whereas floristic composition was different and its abundance was similar. In natural ecosystems, basal area and tree density explained mainly the variation in wealth, diversity and abundance. Not so in pine plantations where horizontal distance to the native forests was the predictor that mostly explained. The greatest diversity of regeneration in natural ecosystems (forests) is associated with the existence of arboreal, shrub and seed biotypes. It is adding to this, efficiency in dispersion processes at the micro-habitat level. These aspects are limiting in plantations of pine, in which the dispersion or availability of seeds depends on the proximity to natural ecosystems.

Structural characterization of Au nano bipyramids: reshaping under thermal annealing, the capping agent effect and surface decoration with Pt.

Anisotropic gold nanoparticles offer potential applications due to their functionalities and shape-dependent properties. Reshaping noble metal nanoparticles is an interesting field with optical, surface-enhanced Raman spectroscopy, catalytic applications and potential application as a photothermic therapy. This work comprises a structural study on gold nano bipyramids (Au NBPs) and nanodumbbells, and the evolution of Au NBPs capped with cetyltrimethylammonium bromide and dodecanethiol through an in situ and ex situ heating process in high vacuum. Also, we study the reshaping of Au NBPs by the addition of Pt to study the surface modification and the strain generated on a single particle by geometric phase analysis.

Synthesis and Properties of the Self-Assembly of Gold-Copper Nanoparticles into Nanoribbons.

We report the efficient wet-chemical production of self-assembled gold-copper bimetallic nanoparticles (diameter of ∼2 nm) into two-dimensional flexible ribbonlike nanostructures. The direct observation of a layered arrangement of particles into nanoribbons was provided through high-resolution transmission electron microscopy and electron tomography. These nanoribbons showed photoluminesce and efficient photocatalytic activity for the conversion of 4-nitrophenol. The thermal stability of the nanoribbons was also measured by in situ heat treatment in the electron microscope, confirming that the self-assembled gold-copper nanoribbons efficiently supported up to 350 °C. The final morphology of the nanoparticles and their ability to self-assemble into flexible nanoribbons were dependent on concentration and the ratio of precursors. Therefore, these experimental factors were discussed. Remarkably, the presence of copper was found to be critical to triggering the self-assembly of nanoparticles into ordered layered structures. These results for the synthesis and stability of self-assemblies of metallic nanoparticles present a potential extension of the method to producing materials with catalytic applications.

Public health impact and economic benefits of quadrivalent influenza vaccine in Latin America.

Annual trivalent influenza vaccines (TIV) containing 2 A strains and one B lineage have been recommended for the prevention of influenza in most of Latin American countries. However, the circulation of 2 B lineages (Victoria and Yamagata) and difficulties in predicting the predominating lineage have led to the development of quadrivalent influenza vaccines (QIV), including both B lineages. Thus, the objective was to estimate the public health impact and influenza-related costs if QIV would have been used instead of TIV in 3 Latin American countries. We used a static model over the seasons 2010-2014 in Brazil, 2007-2014 in Colombia and 2006-2014 in Panama, focusing on population groups targeted by local vaccination recommendations: young children, adults with risk factors and the elderly. In Brazil, between 2010 and 2014, using QIV instead of TIV would have avoided US$ 6,200 per 100,000 person-years in societal costs, based on 168 influenza cases, 89 consultations, 3.2 hospitalizations and 0.38 deaths per 100,000 person-years. In Colombia and Panama, these would have ranged from US$ 1,000 to 12,700 (based on 34 cases, 13-25 consultations, 0.6-8.9 hospitalizations and 0.04-1.74 deaths) and from US$ 3,000 to 33,700 (based on 113 cases, 55-82 consultations, 0.5-27.8 hospitalizations and 0.08-6.87 deaths) per 100,000 person-years, respectively. Overall, the broader protection offered by QIV would have reduced the influenza humanistic and economic burden in the 3 countries. Despite the lack of local data leading to several extrapolations, this study is the first to give quantitative estimates of the potential benefits of QIV in Latin America.

Helical Growth of Ultrathin Gold-Copper Nanowires.

In this work, we report the synthesis and detailed structural characterization of novel helical gold-copper nanowires. The nanowires possess the Boerdijk-Coxeter-Bernal structure, based on the pile up of octahedral, icosahedral, and/or decahedral seeds. They are self-assembled into a coiled manner as individual wires or into a parallel-ordering way as groups of wires. The helical nanowires are ultrathin with a diameter of less than 10 nm and variable length of several micrometers, presenting a high density of twin boundaries and stacking faults. To the best of our knowledge, such gold-copper nanowires have never been reported previously.

Electrum, the Gold-Silver Alloy, from the Bulk Scale to the Nanoscale: Synthesis, Properties, and Segregation Rules.

The alloy Au-Ag system is an important noble bimetallic phase, both historically (as "Electrum") and now especially in nanotechnology, as it is applied in catalysis and nanomedicine. To comprehend the structural characteristics and the thermodynamic stability of this alloy, a knowledge of its phase diagram is required that considers explicitly its size and shape (morphology) dependence. However, as the experimental determination remains quite challenging at the nanoscale, theoretical guidance can provide significant advantages. Using a regular solution model within a nanothermodynamic approach to evaluate the size effect on all the parameters (melting temperature, melting enthalpy, and interaction parameters in both phases), the nanophase diagram is predicted. Besides an overall shift downward, there is a "tilting" effect on the solidus-liquidus curves for some particular shapes exposing the (100) and (110) facets (cube, rhombic dodecahedron, and cuboctahedron). The segregation calculation reveals the preferential presence of silver at the surface for all the polyhedral shapes considered, in excellent agreement with the latest transmission electron microscopy observations and energy dispersive spectroscopy analysis. By reviewing the nature of the surface segregated element of different bimetallic nanoalloys, two surface segregation rules, based on the melting temperatures and surface energies, are deduced. Finally, the optical properties of Au-Ag nanoparticles, calculated within the discrete dipole approximation, show the control that can be achieved in the tuning of the local surface plasmon resonance, depending of the alloy content, the chemical ordering, the morphology, the size of the nanoparticle, and the nature of the surrounding environment.

Gold-copper nanostars as photo-thermal agents: synthesis and advanced electron microscopy characterization.

Nanoalloys have emerged as multi-functional nanoparticles with applications in biomedicine and catalysis. This work reports the efficient production and the advanced transmission electron microscopy characterization of gold-copper pentagonal nanostars. The morphology of the branches is controlled by the adequate choice of the capping agent. When oleylamine is used rounded nanostars are produced, while pointed nanostars are obtained by using hexadecylamine. Both types of nanostars were proved to be thermally stable and could therefore be used as therapeutic agents in photo-thermal therapies as confirmed by the near-infrared absorption spectra.

A cluster-randomised clinical trial comparing two cardiovascular health education strategies in a child population: the Savinghearts project.

BACKGROUND: This paper describes a methodology for comparing the effects of an eduentertainment strategy involving a music concert, and a participatory class experience involving the description and making of a healthy breakfast, as educational vehicles for delivering obesity-preventing/cardiovascular health messages to children aged 7-8 years. METHODS/DESIGN: This study will involve a cluster-randomised trial with blinded assessment. The study subjects will be children aged 7-8 years of both sexes attending public primary schools in the Madrid Region. The participating schools (n=30) will be randomly assigned to one of two groups: 1) Group MC, in which the children will attend a music concert that delivers obesity-preventing/cardiovascular health messages, or 2) Group HB, in which the children will attend a participatory class providing the same information but involving the description and making of a healthy breakfast. The main outcome measured will be the increase in the number of correct answers scored on a knowledge questionnaire and in an attitudes test administered before and after the above interventions. The secondary outcome recorded will be the reduction in BMI percentile among children deemed overweight/obese prior to the interventions. The required sample size (number of children) was calculated for a comparison of proportions with an α of 0.05 and a ß of 0.20, assuming that the Group MC subjects would show values for the measured variables at least 10% higher than those recorded for the subjects of Group HB. Corrections were made for the design effect and assuming a loss to follow-up of 10%. The maximum sample size required will be 2107 children. Data will be analysed using summary measurements for each cluster, both for making estimates and for hypothesis testing. All analyses will be made on an intention-to-treat basis. DISCUSSION: The intervention providing the best results could be recommended as part of health education for young schoolchildren. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01418872.