Estimating water flow through a hillslope using the massively parallel processor

A new two-dimensional model of water flow in a hillslope has been implemented on the Massively Parallel Processor at the Goddard Space Flight Center. Flow in the soil both in the saturated and unsaturated zones, evaporation and overland flow are all modelled, and the rainfall rates are allowed to vary spatially. Previous models of this type had always been very limited computationally. This model takes less than a minute to model all the components of the hillslope water flow for a day. The model can now be used in sensitivity studies to specify which measurements should be taken and how accurate they should be to describe such flows for environmental studies

Distinguishing hypertension from hypertrophic cardiomyopathy as a cause of left ventricular hypertrophy

Distinguishing Hypertension From Hypertrophic Cardiomyopathy as aCause of Left Ventricular HypertrophyIn most hypertensive patients, left ventricular (LV) wallthickness is normal or only mildly increased (≤13 m

Programming a hillslope water movement model on the MPP

A physically based numerical model was developed of heat and moisture flow within a hillslope on a parallel architecture computer, as a precursor to a model of a complete catchment. Moisture flow within a catchment includes evaporation, overland flow, flow in unsaturated soil, and flow in saturated soil. Because of the empirical evidence that moisture flow in unsaturated soil is mainly in the vertical direction, flow in the unsaturated zone can be modeled as a series of one dimensional columns. This initial version of the hillslope model includes evaporation and a single column of one dimensional unsaturated zone flow. This case has already been solved on an IBM 3081 computer and is now being applied to the massively parallel processor architecture so as to make the extension to the one dimensional case easier and to check the problems and benefits of using a parallel architecture machine

Partial adaptation to the value range in the macaque orbitofrontal cortex

Values available for choice in different behavioral contexts can vary immensely. To compensate for this variability, neuronal circuits underlying economic decisions undergo adaptation. In orbitofrontal cortex (OFC), neurons encode the subjective value of offered and chosen goods in a quasilinear way. Previous experiments found that the gain of the encoding is lower when the value range is wider. However, the parameters OFC neurons adapted to remained unclear. Furthermore, previous studies did not examine additive changes in neuronal responses. Computational considerations indicate that these factors can directly impact choice behavior. Here we investigated how OFC neurons adapt to changes in the value range. We recorded from two male rhesus monkeys during a juice choice task. Each session was divided into two blocks of trials. In each block, juices were offered within a set range of values, and ranges changed between blocks. Across blocks, neuronal responses adapted to both the maximum and the minimum value, but only partially. As a result, the minimum neural activity was elevated in some value ranges relative to others. Through simulation of a linear decision model, we showed that increasing the minimum response increases choice variability, lowering the expected payoff. This effect is modulated by the balance between cells with positive and negative encoding. The presence of these two populations induces a non-monotonic relationship between the value range and choice efficacy, such that the expected payoff is highest for decisions in an intermediate value range

Nicotinamide and calcipotriol counteract UVB-induced photoaging on primary human dermal fibroblasts

Background: Photoaging is mainly caused by ultraviolet radiations inasmuch they can damage the DNA, trigger ROS production, and activate p53/p21 pathway, which cause cell cycle arrest and senescence. The accumulationof senescent cells within the dermis contributes to tissue deregulation and skin carcinogenesis. However, the use of photoprotector molecules could reduce UV-induced damages and prevent photoaging. Therefore, the aim of this study is to evaluate whether the active forms of vitamin B3 (nicotinamide) and the analog of vitamin D3 (calcipotriol) might protect primary human dermal fibroblasts (HDFs) from UVB-induced photoaging. Methods: HDFs were isolated from a healthy adult donor and stimulated with nicotinamide (25 μM) and calcipotriol (100 nM) for 24h before UVB exposure, and then, cultured for further 24h on vitamin-supplemented media. Then, cell viability, ROS production, DNA damages, senescence markers, protein and gene expression were evaluated. Results: HDFs treated with nicotinamide and calcipotriol showed better proliferation properties and lower DNA damages due to a reduced UVB-induced ROS production. Consequently, p53/p21 pathway was less active which enhanced cell cycle progression and reduced senescence and cell death. Conclusions: Overall, our results suggest that nicotinamide and calcipotriol can counteract UVB-induced effects responsible for the onset of skin photoaging

SBV regularity for Hamilton-Jacobi equations in Rn\mathbb R^n

In this paper we study the regularity of viscosity solutions to the following Hamilton-Jacobi equations $$\partial_t u + H(D_{x} u)=0 \qquad \textrm{in} \Omega\subset \mathbb R\times \mathbb R^{n} .$$ In particular, under the assumption that the Hamiltonian $H\in C^2(\mathbb R^n)$ is uniformly convex, we prove that $D_{x}u$ and $\partial_t u$ belong to the class $SBV_{loc}(\Omega)$.Comment: 15 page

SFM-MVS photogrammetry for rockfall analysis and hazard assessment along the ancient roman via Flaminia road at the Furlo gorge (Italy)

Rockfall events represent significant hazards for areas characterized by high and steep slopes and therefore effective mitigation controls are essential to control their effect. There are a lot of examples all over the world of anthropic areas at risk because of their proximity to a rock slope. A rockfall runout analysis is a typical 3D problem, but for many years, because of the lack of specific software, powerful computers, and economic reasons, a 2D approach was normally adopted. However, in recent years the use of 3D software has become quite widespread and different runout working approaches have been developed. The contribution and potential use of photogrammetry in this context is undoubtedly great. This paper describes the application of a 3D hybrid working approach, which considers the integrated use of traditional geological methods, Terrestrial Laser Scanning, and drone based Digital Photogrammetry. Such approach was undertaken in order to perform the study of rockfall runout and geological hazard in a natural slope in Italy in correspondence of an archaeological area. Results show the rockfall hazard in the study area and highlights the importance of using photogrammetry for the correct and complete geometrical reconstruction of slope, joints, and block geometries, which is essential for the analysis and design of proper remediation measures