Sph propagation modelling of an earthflow from southern italy

Natural slopes in clayey soils are often affected by failures which may cause the onset of landslides of the flow type travelling large distances and damaging buildings and major infrastructures. Particularly, the so-called earthflows pose challenging tasks for the individuation and forecasting of the remobilized masses; as a consequence, the mathematical modelling of the propagation stage allows enhancing the understanding of earthflows in order to obtain reliable assessments of run-out distances and displaced soil volumes. This paper deals with the reactivations of Montaguto earthflow (Southern Italy) occurred from 1998 to 2009 that are simulated, through the depth-integrated “GeoFlow-SPH” model, thanks to the availability of a detailed data-set. The achieved results provide a satisfactory agreement with the in-situ information and outline how a change of the rheology of the mobilized masses can affect the whole phenomenon

Sustainability assessment of wheat production using Emergy

Sustainability of crop production has to be given high priority when global biomass resources are limited. Here emergy evaluation is applied in order to assess sustainability of crop production exemplified by winter wheat. Emergy evaluation takes into account all inputs involved in a production system (i.e. renewable and non-renewable, local and imported) and transforms them into a common measure of direct and indirect solar energy requirement. The evaluation of winter wheat production is conducted by comparing conventional and organic management on two soil types using Danish reference conditions. The resource use efficiency of wheat production per kg biomass is higher using conventional management practices. This is due to high yield based on large use of non-renewable resources. The environmental loading ratio from organic management practices is about a third of the conventional implying that the organic management can be considered more sustainable

Pion-to-vacuum vector and axial vector amplitudes and weak decays of pions in a magnetic field

We propose a model-independent parametrization for the one-pion-to-vacuum matrix elements of the vector and axial vector hadronic currents in the presence of an external uniform magnetic field. It is shown that, in general, these hadronic matrix elements can be written in terms of several gauge covariant Lorentz structures and form factors. Within this framework we obtain a general expression for the weak decay $\pi^- \to l\,\bar\nu_l$ and discuss the corresponding limits of strong and weak external magnetic fields.Comment: 33 page

Genetic modifiers of cognitive maintenance among older adults.

ObjectiveIdentify genetic factors associated with cognitive maintenance in late life and assess their association with gray matter (GM) volume in brain networks affected in aging.MethodsWe conducted a genome-wide association study of ∼2.4 M markers to identify modifiers of cognitive trajectories in Caucasian participants (N = 7,328) from two population-based cohorts of non-demented elderly. Standardized measures of global cognitive function (z-scores) over 10 and 6 years were calculated among participants and mixed model regression was used to determine subject-specific cognitive slopes. "Cognitive maintenance" was defined as a change in slope of ≥ 0 and was compared with all cognitive decliners (slope < 0). In an independent cohort of cognitively normal older Caucasians adults (N = 122), top association findings were then used to create genetic scores to assess whether carrying more cognitive maintenance alleles was associated with greater GM volume in specific brain networks using voxel-based morphometry.ResultsThe most significant association was on chromosome 11 (rs7109806, P = 7.8 × 10(-8)) near RIC3. RIC3 modulates activity of α7 nicotinic acetylcholine receptors, which have been implicated in synaptic plasticity and beta-amyloid binding. In the neuroimaging cohort, carrying more cognitive maintenance alleles was associated with greater volume in the right executive control network (RECN; PFWE  = 0.01).ConclusionsThese findings suggest that there may be genetic loci that promote healthy cognitive aging and that they may do so by conferring robustness to GM in the RECN. Future work is required to validate top candidate genes such as RIC3 for involvement in cognitive maintenance

Discipline‐centered post‐secondary science education research: Distinctive targets, challenges and opportunities

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108082/1/tea21165.pd

Hormigón fabricado con asfalto triturado como reemplazo parcial de áridos naturales

The paper focuses on the reuse of crushed asphalt (GA) as a partial replacement (up to 20%) of natural aggregates for concrete manufacture. Addition of GA aggregates produced a positive effect on workability loss. The GA mixes, however, showed a significant tendency to bleed and segregate at the highest replacement percentage applied. GA led to a decrease of compressive strength in concrete (with respect to that of the reference concrete) up to 50% due to the weakness of the cement paste / recycled aggregate interface. To compensate for this negative effect, a reduction of w/c for the GA concretes was necessary. A decrease of w/c allowed the GA concretes to show drying shrinkage values substantially similar to those of reference concrete with the same cement factor. The experimental results confirmed the possibility of partial substitution (max. 15%) of natural aggregates with crushed asphalt for making concrete.El artículo se centra en la reutilización del asfalto triturado (AM) como reemplazo parcial (hasta 20%) de áridos naturales para la fabricación de hormigón. Los áridos de AM además produjeron un efecto positivo sobre la pérdida de la trabajabilidad. Las mezclas de AM mostraron una marcada tendencia a la exudación y segregación en el más elevado porcentaje de sustitución. El AM condujo a una disminución de la resistencia a la compresión en el hormigón (con respecto al hormigón de referencia) de hasta un 50% debido a la debilidad de la pasta de cemento. Para compensar este efecto, fue necesaria una reducción de agua-cemento (a/c) para hormigones AM. Se consiguieron valores de retracción de secado sustancialmente similares a los de hormigón de referencia con el mismo contenido de cemento. Los resultados experimentales confirmaron la posibilidad de sustitución parcial (máximo 15%) de áridos naturales por asfalto triturado para la fabricación de hormigón

The Role of Written and Verbal Expression in Improving Communication Skills for Students in an Undergraduate Chemistry Program

Proofreading, editing, and critique, the customary assessment tools scientists use to evaluate professional journal articles, grant applications, and any other writing, can be applied equally well in introductory science instruction. Such feedback is, in fact, crucial to growth and development. When learning anything new, students and faculty alike rely heavily on sources other than themselves (‘external editors’) to assess their understanding as they develop self-assessment skills (or ‘internal editors’). Although they rarely describe it in these terms, faculty nonetheless assume that students have developed and refined their internal skills by the time they take examinations and write term papers. Unfortunately, science instructors traditionally provide little meaningful assistance or rationale for students to get to that point. This is in part because we faculty have already developed and deploy our professional skills so tacitly. To a degree, individuals who become faculty members probably follow paths of least resistance, the ones along which they were successful by virtue of their ‘natural aptitude’. What some instructors intend to be their best advice to students can be wholly inadequate if it only reflects on the surface aspects of what they did as students: “do lots of problems,” “write lots of prose,” “sit alone and wrestle with the ideas.” One of the things we faculty do quite naturally in our professional lives is to rely on external input. Having developed any idea to whatever limit we are able to achieve sitting alone in our workplaces with our internal editors and our reference sources, we next try out the ideas on our colleagues. Expressing our understanding to others is always a teaching activity since we are revealing our interpretation of some aspect of the world to another individual, testing the interpretation against another’s point-of-view. Faculty share a common experience that they describe in familiar terms: “I never really learned it until I had to teach it.” Perhaps what we also mean is that we actually think about our ideas in new ways when we are consciously aware of the fact that we need to describe them to someone else. In writing as well as speaking, attention to the needs of the audience is critical to clarity in the expression of meaning through the use of information (1). Learners learn differently, perhaps even more effectively, when they anticipate the need to express their understanding to someone else. For students, the most common example of this type of anticipation is in preparation for a written or oral examination. This perspective is not at all limited to expository writing and speaking, the usual modes of expression in the physical sciences; revealing internal perspectives represents +expression+ regardless of its modality, and does not favor writers and orators over thespians, pianists, painters, ballerinas or chanteurs

Electronic States in Diffused Quantum Wells

In the present study we calculate the energy values and the spatial distributions of the bound electronic states in some diffused quantum wells. The calculations are performed within the virtual crystal approximation, $sp^3 s^*$ spin dependent empirical tight-binding model and the surface Green function matching method. A good agreement is found between our results and experimental data obtained for AlGaAs/GaAs quantum wells with thermally induced changes in the profile at the interfaces. Our calculations show that for diffusion lengths $L_{D}=20\div100$ {\AA} the transition (C3-HH3) is not sensitive to the diffusion length, but the transitions (C1-HH1), (C1-LH1), (C2-HH2) and (C2-LH2) display large "blue shifts" as L_{D} increases. For diffusion lengths $L_{D}=0\div20$ {\AA} the transitions (C1-HH1) and (C1-LH1) are less sensitive to the L_{D} changes than the (C3-HH3) transition. The observed dependence is explained in terms of the bound states spatial distributions.Comment: ReVTeX file, 7pp., no macros, 4 figures available on the reques