Proposal for improved mixes to produce concrete masonry units with commonly used aggregates available in the Valley of Mexico

Proposal for improved mixes to produce concrete masonry units with commonly used aggregates available in the Valley of MexicoABSTRACTIn this paper, a proposal is done to update the masonry index compressive strength design value f*m for solid concrete masonry units for the masonry guidelines of Mexico´s Federal District Code (NTCM-2004). Solid units were made by taking into account the characteristics of the most commonly used raw materials available in the Valley of Mexico to fabricate such units in the Metropolitan Area of Mexico City. Different tests were conducted for both raw materials and the obtained concrete units. Based upon test results, it is illustrated why it is much better to design masonry structures based upon the experimental data of the units to be used at the construction site rather than using index values proposed in building codes.Keywords: masonry; concrete masonry units; compressive strength.Propuesta de mejora de mezclas para producir piezas de mampostería de concreto empleando materiales comúnmente disponibles en el Valle de MéxicoRESUMENSe presenta un estudio donde se hace una propuesta para actualizar los valores índices de la resistencia a la compresión de mamposterías (f*m) elaboradas con piezas de concreto especificados en las normas de mampostería vigentes en el Distrito Federal. Se realizó un estudio de mercado, donde se tomaron en cuenta las características de los materiales comúnmente utilizados en la actualidad en el Valle de México para la fabricación de piezas de concreto sólidas, incluyendo los resultados de distintas pruebas de laboratorio realizadas a la materia prima. Con base en estos resultados, se ilustran las ventajas de diseñar a la mampostería con base experimental en lugar de utilizar los valores indicativos que se ofrecen en las normas de mampostería.Palabras clave: mampostería; piezas de concreto; resistencia a la compresión. Proposta de melhoria de traços para produzir blocos de alvenaria de concreto utilizando materiais comumente disponíveis no Vale do México RESUMOApresenta-se um estudo onde se propõe uma atualização dos valores do índice de resistência à compressão da alvenaria (f*m) elaborados com blocos de concreto especificados nas normas de alvenaria em vigor no Distrito Federal. Foi realizado um estudo de mercado, que levou em conta as características dos materiais comumente utilizados atualmente no Vale do México para a fabricação de blocos de concreto sólidos, incluindo os resultados de vários testes de laboratório nas matérias-primas disponíveis. Com base nestes resultados, são apresentadas as vantagens de projetar a alvenaria com base experimental em lugar de usar os valores indicativos oferecidos nas normas de alvenaria.Palavras chave: alvenaria; blocos de concreto; resistência à compressão.

Electromagnetic polarization-controlled perfect switching effect with high-refractive-index dimers and the beam-splitter configuration

Sub-wavelength particles made from high-index dielectrics, either individual or as ensembles, are ideal candidates for multifunctional elements in optical devices. Their directionality effects are traditionally analysed through forward and backward measurements, even if these directions are not convenient for in-plane scattering practical purposes. Here we present unambiguous experimental evidence in the microwave range that for a dimer of HRI spherical particles, a perfect switching effect is observed out of those directions as a consequence of the mutual particle electric/magnetic interaction. The binary state depends on the excitation polarization. Its analysis is performed through the linear polarization degree of scattered radiation at a detection direction perpendicular to the incident direction: the beam-splitter configuration. The scaling property of Maxwell's equations allows the generalization of our results to other frequency ranges and dimension scales, for instance, the visible and the nanometric scale.

Traditional metallic communication elements suffer from substantial losses in the visible and near-infrared. Here, Barreda et al. show in a proof of principle in the microwave regime that a pair of high-index dielectric spheres can operate as a perfect switch in a beam-splitter configuration.

Extension of the Kubelka-Munk theory to an arbitrary substrate: a Monte Carlo approach

In this work we review and-to some extent-upgrade one of the main theories of light flux through homogeneous isotropic media, namely, the Kubelka-Munk (K-M) theory, and in particular the later expansion made by Kubelka to obtain the reflectance of a specimen when a substrate lies underneath. We have completed this solution by calculating the transverse energy density in the specimen and the transmission of the whole. We show that this last result-compatible with Kubelka's upgrade for layered media-also allows for the calculation of the specimen/substrate absorption split. In order to validate these expressions, the results were reproduced by means of a Monte Carlo simulation working on a layered medium under the same assumptions as the K-M theory. Interestingly, the numerical procedure introduces new capabilities in the model regarding the history of any absorbed or outgoing elemental light beam, such as the recording of its time-of-flight through a given system.

A Functional Link between AMPK and Orexin Mediates the Effect of BMP8B on Energy Balance

AMP-activated protein kinase (AMPK) in the ventromedial nucleus of the hypothalamus (VMH) and orexin (OX) in the lateral hypothalamic area (LHA) modulate brown adipose tissue (BAT) thermogenesis. However, whether these two molecular mechanisms act jointly or independently is unclear. Here, we show that the thermogenic effect of bone morphogenetic protein 8B (BMP8B) is mediated by the inhibition of AMPK in the VMH and the subsequent increase in OX signaling via the OX receptor 1 (OX1R). Accordingly, the thermogenic effect of BMP8B is totally absent in ox-null mice. BMP8B also induces browning of white adipose tissue (WAT), its thermogenic effect is sexually dimorphic (only observed in females), and its impact on OX expression and thermogenesis is abolished by the knockdown of glutamate vesicular transporter 2 (VGLUT2), implicating glutamatergic signaling. Overall, our data uncover a central network controlling energy homeostasis that may be of considerable relevance for obesity and metabolic disorders.

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Central BMP8B modulates BAT thermogenesis and browning of WAT

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AMPK in the VMH mediates central BMP8B actions

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OX in the LHA mediates central BMP8B actions

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The AMPK(VMH)-OX(LHA) axis is a functional neuronal pathway regulating energy balance

Polarimetric response of magnetodielectric core-shell nanoparticles: an analysis of scattering directionality and sensing

The influence of increasing the core size of Ag-Si core-shell nanoparticles has been investigated by using the values of the linear polarization degree at a right-angle scattering configuration, [Formula: see text]. Changes in dipolar resonances and scattering directionality conditions as a function of the core radius (R int) for a fixed shell size ([Formula: see text] nm) have been analysed. An empirical formula to obtain the ratio [Formula: see text] by monitoring the influence of the magnetic dipolar resonance in [Formula: see text] has been found. The effect of the refractive index of the surrounding medium, m med, in the zero backward and almost-zero forward scattering conditions has also been studied. We have weighed up the sensitivity of [Formula: see text] to m med. It has been demonstrated that multipolar contributions strongly influence [Formula: see text]. This influence can be used as a fast m med estimate. In all cases, the results show that the bigger the cores, the higher the sensitivity to m med.

Seroprevalence in Household Raised Pigs Indicate High Exposure to GII Noroviruses in Rural Nicaragua

Information about porcine norovirus (PoNoV), genetically similar to human NoV (HuNoV), is limited from rural areas where household-raised pigs are heavily exposed to faecal material which could facilitate transmission. Histo-blood group antigens (HBGAs) are known susceptibility factors to NoV in humans and in a germfree piglet model but their role in susceptibility in the porcine population remains unknown. This study reports: (i) the seroprevalence and antibody titres to human norovirus (NoV) VLPs in household raised pigs; (ii) the distribution of HBGAs in relation to NoV IgG antibody titres and further characterization by blocking of GII.4 VLP binding to pig gastric mucins (PGM). The majority of pigs were seropositive to all three VLPs tested (58-70%) with seropositivity and cross-reactivity increasing significantly with age. However, pig sera could not block the binding of NoV GII.4 VLPs (Dijon) to PGM suggesting no previous infection with this genotype. The majority of the pigs were H-positive (84%), a susceptibility factor for human infections. IgG antibody titres were however higher in H-negative (GMT = 247) as compared with H-positive (GMT = 57) pigs, but after age stratification, this difference in antibody titres was only observed in pigs ≤1 month of age. In conclusion, serological data show that the porcine population of Nicaragua is highly exposed to NoV infections, and the association to HBGAs warrants further investigation.

[Surveillance in Spain 3 years since the enactment of the Public Health Law]

In 2014, the Epidemiological Surveillance Working Group of the Sociedad Española de Epidemiología (Spanish Society of Epidemiology), carried out a descriptive study in order to evaluate the level of development of the Spanish Public Health Law since its enactment in 2011. A survey collecting data on the existence of information systems and other aspects pertaining to each surveillance section included in the law was sent to all 19 autonomous communities and cities. All regional authorities reported the presence of an information system for communicable diseases, and six also reported an information system for social factors. 18 reported that at least one chronic disease was subject to surveillance and 14 confirmed surveillance of some of its determinants. They all systematically analysed the data derived from the communicable diseases. There is room for improvement in Public Health surveillance in Spain, and action should be aimed at the main health problems.

Near- and far-field scattering resonance frequency shift in dielectric and perfect electric conducting cylinders

The ability to infer near-field scattering properties from far-field measurements is of paramount importance in nano-optics. Recently we derived an approximate formula for predicting the frequency shift between near- and far-field intensity peaks in the case of a dielectric sphere. In this work we demonstrate that almost an identical formula can be used to predict the resonance shift of a dielectric cylinder and a perfectly conducting cylinder. We find the redshift of the resonance peak of the perfect electric conducting cylinder to be approximately 2 orders of magnitude greater than for the dielectric cylinder. The errors in our approximate analytic formula for predicting the redshift are approximately only twice as great. Furthermore, we apply the redshift formula to a silicon cylinder and discuss its magneto-dielectric properties, which may be of interest in design of metamaterials.

Size-tunable rhodium nanostructures for wavelength-tunable ultraviolet plasmonics

Polydisperse rhodium nanoparticles have recently shown promise for ultraviolet (UV) plasmonics, but controlling the size and morphology of metal nanoparticles is essential for tuning surface plasmon resonances. Here we report the use of slow-injection polyol methods to synthesize monodisperse Rh nanocubes with unprecedentedly large sizes and slightly concave faces. The associated local surface plasmon resonances (LSPRs) red-shifted with increasing sizes in the UV region from deep UV to around 400 nm, consistent with numerical simulations. UV illumination of p-aminothiophenol attached to the Rh nanocubes generated surface-enhanced Raman spectra and accelerated photo-decomposition, and these enhancements were largest for nanocubes whose LSPR was resonant with the UV laser. The lack of a native oxide coating, the precise control of nanocube size and morphology demonstrated here, and the ability to tune the surface plasmon resonance from the deep UV to near UV spectral region, make rhodium a compelling choice for UV plasmonic applications.

Frequency shift between near- and far-field scattering resonances in dielectric particles

The near-field electromagnetic scattering intensity resonances are redshifted in frequency with respect to their far-field counterparts. We derive simple, approximate, analytical formulas for this shift in the case of a plane wave interacting with a dielectric sphere. Numerical results comparing the approximate formulas to the numerically exact solutions show that the two are in good agreement. We also consider the Rayleigh limit of the formulas to gain more insight into the phenomenon.

Induction of hyperandrogenism in lean reproductive-age women stimulates proatherogenic inflammation

We determined the effect of hyperandrogenemia as observed in polycystic ovary syndrome (PCOS) on fasting and glucose-stimulated proatherogenic inflammation markers in lean healthy reproductive-age women. Sixteen lean healthy ovulatory reproductive-age women were treated with 130 mg of DHEA or placebo (n=8 each) for 5 days. Interleukin-6 (IL-6) mRNA and IL-6 release from mononuclear cells (MNC), plasma IL-6 and C-reactive protein (CRP), and MNC-derived (matrix metalloproteinase-2) MMP-2 protein were quantified in the fasting state and 2 h after glucose ingestion, before and after treatment. Before treatment, subjects receiving dehydroepinadrosterone (DHEA) or placebo exhibited no differences in androgens, or any proatherogenic inflammation markers while fasting and after glucose ingestion. Compared with placebo, DHEA administration raised levels of testosterone, androstenedione, and DHEA-sulfate (DHEA-S), and increased the percent change from baseline in fasting IL-6 mRNA, IL-6 release, plasma IL-6, and CRP and MMP-2 protein. However, there were no differences in any of the proatherogenic inflammation markers following glucose ingestion after DHEA administration. We conclude that in lean reproductive-age women, proatherogenic inflammation in the fasting state increases after raising circulating androgens to levels observed in PCOS. However, this hyperandrogenemia-induced MNC activation does not provoke a similar response to subsequent glucose ingestion.

Using linear polarization for sensing and sizing dielectric nanoparticles

The spectral evolution of the degree of linear polarization (PL) at a scattering angle of 90° is studied numerically for high refractive index (HRI) dielectric spherical nanoparticles. The behaviour of PL(90°) is analysed as a function of the refractive index of the surrounding medium and the particle radius, and it is compared with the more conventional extinction efficiency parameter (Qext), usually used for sensing applications. We focus on the spectral region where both electric and magnetic resonances of order not higher than two are located for various semiconductor materials with low absorption. Although both Qext and PL(90°) are identifiers of the refractive index of the surrounding medium, the spectral of PL(90°) has only a small, linear dependence on nanoparticle size R. This weak dependence makes it experimentally feasible to perform real-time retrievals of both the refractive index of the external medium and the NP size R.

Rhodium nanoparticles for ultraviolet plasmonics

The nonoxidizing catalytic noble metal rhodium is introduced for ultraviolet plasmonics. Planar tripods of 8 nm Rh nanoparticles, synthesized by a modified polyol reduction method, have a calculated local surface plasmon resonance near 330 nm. By attaching p-aminothiophenol, local field-enhanced Raman spectra and accelerated photodamage were observed under near-resonant ultraviolet illumination, while charge transfer simultaneously increased fluorescence for up to 13 min. The combined local field enhancement and charge transfer demonstrate essential steps toward plasmonically enhanced ultraviolet photocatalysis.

Telemedicine system for the care of patients with neuromuscular disease and chronic respiratory failure

INTRODUCTION

Neuromuscular diseases cause a number of limitations which may be improved by using a telemedicine system. These include functional impairment and dependence associated with muscle weakness, the insidious development of respiratory failure and episodes of exacerbation.

MATERIAL AND METHODS

The present study involved three patients with severe neuromuscular disease, chronic respiratory failure and long-term mechanical ventilation, who were followed up using a telemedicine platform. The telemedicine system is based on videoconferencing and telemonitoring of cardiorespiratory variables (oxygen saturation, heart rate, blood pressure and electrocardiogram). Two different protocols were followed depending on whether the patient condition was stable or unstable.

RESULTS

Over a period of 5 years, we analyzed a series of variables including use of the system, patient satisfaction and clinical impact. Overall we performed 290 videoconference sessions, 269 short monitoring oximetry measurements and 110 blood pressure measurements. With respect to the clinical impact, after enrolment in the telemedicine program, the total number of hospital admissions fell from 18 to 3.

CONCLUSIONS

Our findings indicate that the system was user friendly for patients and care givers. Patient satisfaction scores were acceptable. The telemedicine system was effective for the home treatment of three patients with severe neuromuscular diseases and reduced the need for hospital admissions.