Enhancement of photoacoustic detection of inhomogeneities in polymers

We report a series of experiments on laser pulsed photoacoustic excitationin turbid polymer samples addressed to evaluate the sound speed in the samples and the presence of inhomogeneities in the bulk. We describe a system which allows the direct measurement of the speed of the detected waves by engraving the surface of the piece under study with a fiduciary pattern of black lines. We also describe how this pattern helps to enhance the sensitivity for the detection of an inhomogeneity in the bulk. These two facts are useful for studies in soft matter systems including, perhaps, biological samples. We have performed an experimental analysis on Grilon(R) samples in different situations and we show the limitations of the method.Comment: 8 pages, 7 figure

Analogue mouse pointer control via an online steady state visual evoked potential (SSVEP) brain-computer interface

The steady state visual evoked protocol has recently become a popular paradigm in brain–computer interface (BCI) applications. Typically (regardless of function) these applications offer the user a binary selection of targets that perform correspondingly discrete actions. Such discrete control systems are appropriate for applications that are inherently isolated in nature, such as selecting numbers from a keypad to be dialled or letters from an alphabet to be spelled. However motivation exists for users to employ proportional control methods in intrinsically analogue tasks such as the movement of a mouse pointer. This paper introduces an online BCI in which control of a mouse pointer is directly proportional to a user's intent. Performance is measured over a series of pointer movement tasks and compared to the traditional discrete output approach. Analogue control allowed subjects to move the pointer faster to the cued target location compared to discrete output but suffers more undesired movements overall. Best performance is achieved when combining the threshold to movement of traditional discrete techniques with the range of movement offered by proportional control

P-model v1.0: an optimality-based light use efficiency model for simulating ecosystem gross primary production

Terrestrial photosynthesis is the basis for vegetation growth and drives the land carbon cycle. Accurately simulating gross primary production (GPP, ecosystem-level apparent photosynthesis) is key for satellite monitoring and Earth System Model predictions under climate change. While robust models exist for describing leaf-level photosynthesis, predictions diverge due to uncertain photosynthetic traits and parameters which vary on multiple spatial and temporal scales. Here, we describe and evaluate a gross primary production (GPP, photosynthesis per unit ground area) model, the P-model, that combines the Farquhar-von Caemmerer-Berry model for C3 photosynthesis with an optimality principle for the carbon assimilation- transpiration trade-off, and predicts a multi-day average light use efficiency (LUE) for any climate and C3 vegetation type. The model is forced here with satellite data for the fraction of absorbed photosynthetically active radiation and site-specific meteorological data and is evaluated against GPP estimates from a globally distributed network of ecosystem flux measurements. Although the P-model requires relatively few inputs and prescribed parameters, the R2 for predicted versus observed GPP based on the full model setup is 0.75 (8-day mean, 131 sites) – better than some state-of-the-art satellite data-driven light use efficiency models. The R2 is reduced to 0.69 when not accounting for the reduction in quantum yield at low temperatures and effects of low soil moisture on LUE. The R2 for the P-model-predicted LUE is 0.37 (means by site) and 0.53 (means by vegetation type). The P-model provides a simple but powerful method for predicting – rather than prescribing light use efficiency and simulating terrestrial photosythesis across a wide range of conditions. The model is available as an R package (rpmodel)

Deformación plástica del antebrazo: revisión y caso clínico

La deformidad plástica de un hueso es una rara entidad, que en ocasiones pasa desapercibida. Se trata de una lesión típica del niño, con un hueso más elástico que los adultos. La mayoría de las deformidades plásticas del antebrazo se producen por caídas con el brazo en extensión, causando deformidad, dolor y una limitación de la pronosupinación. Para reducir la curvatura del hueso se precisan fuerzas contrarias a las que produjeron la lesión, mantenidas en el tiempo. En niños menores de 4 años, con enorme capacidad de remodelación, sólo grandes deformidades >20º deberían ser reducidas. En los mayores de 10 años, con escaso potencial remodelador, deben manipularse aquellas angulaciones >10-15º. La mayor complicación derivada de una mala reducción es la limitación de la pronosupinación, que en la mayoría de las ocasiones no altera la funcionalidad de la extremidad.Plastic bowing of a bone is a rare entity that some- times goes unnoticed. It’s a typical injury in children, who have more elastic bones than adults. Most of the plastic bowing of the forearm take place by falls with an outstretched arm, causing deformities, pain and a limitation of pronation and supination. In order to reduce the curvature of the bone, opposing forces to those that produced the injury are needed, maintained for a long time. In children younger than 4 years, with an enormous remodelling capacity, only great deformi- ties >20º should be reduced. For those older than 10 years, with little remodelling capacity, angulations >10-15º must be manipulated. The greatest complication derived from a bad reduction is the limitation of the pronation and supination, which in most cases does not modify the functionality of the extremity

P1 Height in Hispanics With and Without Family History of Type 2 Diabetes

Coronary heart disease (CHD) is the world’s leading cause of death, with type 2 diabetes (T2D) increasing that risk ~3-fold. T2D incidence in Hispanics of the Rio Grande Valley (RGV) is \u3e27% vs 9% noted nationwide. Further, having a family history of T2D (FH+) increases risk by ~40%. PURPOSE: To determine if specific aspects of macrovascular function may precede overt hypertension and T2D in FH+ people in the RGV. METHODS: Thirty-three healthy individuals, including 10 FH+ and 23 FH- (26 ± 7; 24 ± 5 yrs respectively), participated in this study. Hemodynamics and large artery function were assessed at rest. One-way ANOVA was used to determine group differences. Pearson correlation was used to determine relationships between significant variables. RESULTS: P1 Height, a measure of forward vascular pressure generated by ventricular contraction, was higher (pCONCLUSIONS: P1 Height is elevated in FH+ individuals and is related to some variables of positive health status, such as triglycerides and lower body fat. More studies are warranted to determine if P1 height is cardioprotective, or a pathophysiological precedent to hypertension

Enhancement of photoacoustic detection of inhomogeneities in polymers

We report a series of experiments on laser pulsed photoacoustic excitation in turbid polymer samples addressed to evaluate the sound speed in the samples and the presence of inhomogeneities in the bulk. We describe a system which allows the direct measurement of the speed of the detected waves by engraving the surface of the piece under study with a fiduciary pattern of black lines. We also describe how this pattern helps to enhance the sensitivity for the detection of an inhomogeneity in the bulk. These two facts are useful for studies in soft matter systems including, perhaps, biological samples. We have performed an experimental analysis on Grilon®samples in different situations and we show the limitations of the method.Facultad de Ingenierí

Population History and Gene Divergence in Native Mexicans Inferred from 76 Human Exomes.

Native American genetic variation remains underrepresented in most catalogs of human genome sequencing data. Previous genotyping efforts have revealed that Mexico's Indigenous population is highly differentiated and substructured, thus potentially harboring higher proportions of private genetic variants of functional and biomedical relevance. Here we have targeted the coding fraction of the genome and characterized its full site frequency spectrum by sequencing 76 exomes from five Indigenous populations across Mexico. Using diffusion approximations, we modeled the demographic history of Indigenous populations from Mexico with northern and southern ethnic groups splitting 7.2 KYA and subsequently diverging locally 6.5 and 5.7 KYA, respectively. Selection scans for positive selection revealed BCL2L13 and KBTBD8 genes as potential candidates for adaptive evolution in Rarámuris and Triquis, respectively. BCL2L13 is highly expressed in skeletal muscle and could be related to physical endurance, a well-known phenotype of the northern Mexico Rarámuri. The KBTBD8 gene has been associated with idiopathic short stature and we found it to be highly differentiated in Triqui, a southern Indigenous group from Oaxaca whose height is extremely low compared to other Native populations

On the origin of the Norwegian lemming.

The Pleistocene glacial cycles resulted in significant changes in species distributions, and it has been discussed whether this caused increased rates of population divergence and speciation. One species that is likely to have evolved during the Pleistocene is the Norwegian lemming (Lemmus lemmus). However, the origin of this species, both in terms of when and from what ancestral taxon it evolved, has been difficult to ascertain. Here, we use ancient DNA recovered from lemming remains from a series of Late Pleistocene and Holocene sites to explore the species' evolutionary history. The results revealed considerable genetic differentiation between glacial and contemporary samples. Moreover, the analyses provided strong support for a divergence time prior to the Last Glacial Maximum (LGM), therefore likely ruling out a postglacial colonization of Scandinavia. Consequently, it appears that the Norwegian lemming evolved from a small population that survived the LGM in an ice-free Scandinavian refugium