Shock metamorphism in plagioclase and selective amorphization

Plagioclase feldspar is one of the most common rock‐forming minerals on the surfaces of the Earth and other terrestrial planetary bodies, where it has been exposed to the ubiquitous process of hypervelocity impact. However, the response of plagioclase to shock metamorphism remains poorly understood. In particular, constraining the initiation and progression of shock‐induced amorphization in plagioclase (i.e., conversion to diaplectic glass) would improve our knowledge of how shock progressively deforms plagioclase. In turn, this information would enable plagioclase to be used to evaluate the shock stage of meteorites and terrestrial impactites, whenever they lack traditionally used shock indicator minerals, such as olivine and quartz. Here, we report on an electron backscatter diffraction (EBSD) study of shocked plagioclase grains in a metagranite shatter cone from the central uplift of the Manicouagan impact structure, Canada. Our study suggests that, in plagioclase, shock amorphization is initially localized either within pre‐existing twins or along lamellae, with similar characteristics to planar deformation features (PDFs) but that resemble twins in their periodicity. These lamellae likely represent specific crystallographic planes that undergo preferential structural failure under shock conditions. The orientation of preexisting twin sets that are preferentially amorphized and that of amorphous lamellae is likely favorable with respect to scattering of the local shock wave and corresponds to the “weakest” orientation for a specific shock pressure value. This observation supports a universal formation mechanism for PDFs in silicate minerals

Epidemics in partially overlapped multiplex networks

Many real networks exhibit a layered structure in which links in each layer reflect the function of nodes on different environments. These multiple types of links are usually represented by a multiplex network in which each layer has a different topology. In real-world networks, however, not all nodes are present on every layer. To generate a more realistic scenario, we use a generalized multiplex network and assume that only a fraction $q$ of the nodes are shared by the layers. We develop a theoretical framework for a branching process to describe the spread of an epidemic on these partially overlapped multiplex networks. This allows us to obtain the fraction of infected individuals as a function of the effective probability that the disease will be transmitted $T$. We also theoretically determine the dependence of the epidemic threshold on the fraction $q > 0$ of shared nodes in a system composed of two layers. We find that in the limit of $q \to 0$ the threshold is dominated by the layer with the smaller isolated threshold. Although a system of two completely isolated networks is nearly indistinguishable from a system of two networks that share just a few nodes, we find that the presence of these few shared nodes causes the epidemic threshold of the isolated network with the lower propagating capacity to change discontinuously and to acquire the threshold of the other network.Comment: 13 pages, 4 figure

Star formation history of KDG 61 and KDG 64 from spectroscopy and colour-magnitude diagrams

A study of two dE/dSph members of the nearby M 81 group of galaxies, KDG 61 and UGC 5442 = KDG 64, has been made. Direct Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) images and integrated-light spectra of 6 m telescope of Special Astrophysical Observatory of Russian Academy of Sciences have been used for quantitative star formation history analysis. The spectroscopic and colour-magnitude diagrams analysis gives consistent results. These galaxies appear to be dominated by an old population (12-14 Gyr) of low metallicity ([Fe/H]~-1.5). Stars of ages about 1 to 4 Gyr have been detected in both galaxies. The later population shows marginal metal enrichment. We do not detect any significant radial gradients in age or metallicity in these galaxies. Our radial velocity measurement suggests that the HII knot on the line-of-sight of KDG 61 is not gravitationally attached to the galaxy.Comment: 16 pages, 13 figures, accepted by MNRA

Planeamiento estratégico para el distrito de San Borja

El distrito de San Borja está ubicado en Lima Metropolitana, al centro oeste del Perú, con una población de 111,928 habitantes y una densidad poblacional de 11,290 personas por kilómetro cuadrado. El distrito se ha destacado por un rápido crecimiento en centros comerciales y por ser el tercero del área metropolitana en cuanto a la cantidad de licencias de construcción que otorga anualmente. Pero tal situación se ha dado en un contexto donde no se han ampliado las vías de tránsito y existe inseguridad, a pesar de contar con centros de control de imágenes y vigilancia. Para el año 2030, se tendrá un distrito seguro con rápido crecimiento en el ámbito comercial, empresarial y residencial, al contar con instituciones de educación superior de alta calidad y áreas verdes que permitirán diferenciarse de otros distritos limeños. Esto se alcanzará mediante la implementación de estrategias que se crearon en el marco de la Matriz FODA y que fueron evaluadas con distintas herramientas. Dentro de estas herramientas se contemplan aspectos como el desarrollo de un servicio integrado de transporte municipal, que se conecte con el tren eléctrico que ya circula por el distrito y con la nueva red. Al tener un método de transporte eficiente, brindar seguridad y servicios educativos, el distrito se hará más atractivo para la inversión en centros comerciales y en edificios residenciales inteligentes, que favorecerán el cuidado del medio ambiente; al mismo tiempo que se mejorará la calidad de vida de las personas. Esto debe conducir a la constitución de más empresas y el establecimiento de universidades de prestigio, para promover que los pobladores laboren y estudien en el mismo distrito; lo que incrementará el uso de las ciclovías y el cuidado de las áreas verdesSan Borja district is located in Lima Metropolitan area, in the center of western Peru, with a population of 111,928 inhabitants and a population density of 11,290 people per square kilometer. The district has been notable for rapid growth in shopping malls as well as being the third largest metropolitan area in terms of the number of construction licenses it grants annually. But this has occurred in a context where the transit routes have not been expanded and there is a presence of insecurity, despite having centers for image control and surveillance. By 2030 there will be a safe district with rapid growth in the commercial, business and residential areas, with high quality institutions of higher education and green areas that will allow to differentiate itself from other districts in the capital. This will be achieved through the implementation of strategies developed within SWOT analysis and followed by a complete evaluation. They include different areas as the development of an integrated municipal transportation system, making easier to connect the whole district with the metropolitan electrical train. This will contribute to attract higher investments for commercial areas or malls as well as for multi-family residences, providing efficiency and using construction technics for a sustainable development. The main purpose is that population makes all their activities inside the same district, spending short time in transportation, using bicycles and enjoying parks while they have access to excellent educational servicesTesi

Single-cell analysis resolves the cell state transition and signaling dynamics associated with melanoma drug-induced resistance

Continuous BRAF inhibition of BRAF mutant melanomas triggers a series of cell state changes that lead to therapy resistance and escape from immune control before establishing acquired resistance genetically. We used genome-wide transcriptomics and single-cell phenotyping to explore the response kinetics to BRAF inhibition for a panel of patient-derived BRAF^(V600)-mutant melanoma cell lines. A subset of plastic cell lines, which followed a trajectory covering multiple known cell state transitions, provided models for more detailed biophysical investigations. Markov modeling revealed that the cell state transitions were reversible and mediated by both Lamarckian induction and nongenetic Darwinian selection of drug-tolerant states. Single-cell functional proteomics revealed activation of certain signaling networks shortly after BRAF inhibition, and before the appearance of drug-resistant phenotypes. Drug targeting those networks, in combination with BRAF inhibition, halted the adaptive transition and led to prolonged growth inhibition in multiple patient-derived cell lines

Predicting ICU Admissions from Attempted Suicide Presentations at an Emergency Department in Central Queensland, Australia

BackgroundEmergency medicine physicians and psychiatric staff face a challenging job in risk stratifying patients presenting with suicide attempts to predict which patients need intensive care unit admission, hospital admission or can be discharged with psychiatry follow up.AimsThis study aims to analyse patients who were admitted to the intensive care unit or regular ward for suicide attempt, and the methods they employed in a rural Australian base hospital.MethodWe conducted a retrospective analysis of patients who presented with suicide attempts to the Rockhampton Base Hospital Emergency Department, Queensland Australia from 1 September 2007 to 31 August 2009. Multivariate logistic regression was undertaken to identify risk factors for ICU and regular ward admission, and predictors of suicide method.ResultsThere were 570 patients presenting with suicide attempts, 74 of which were repeat suicide attempts. There was a 10-fold increase in the odds of intensive care unit or ICU admission (CI 1.45-81.9, p=0.02) for patients who presented with drug overdose. Increased age (OR=1.02, 95 per cent CI 1.00-1.03, p=0.05), drug overdose (OR=2.69, 95 per cent CI 1.37-5.29, p=0.004), and previous suicide attempt (OR=1.53, 95 per cent CI 1.03-2.28, p=0.03) were significantly correlated with hospital admission. Male patients (OR=2.76, 95 per cent CI 1.43-5.30, p=0.002) and Aboriginal patients (OR=3.38, 95 per cent CI 1.42-8.05, p=0.006) were more likely to choose hanging as a suicide method.ConclusionWe identified drug overdose as a strong predictor of ICU admission, while age, drug overdose and history of previous suicide attempts predict hospital admission. We recommend reviewing physician practices, especially safe medication, in suicide risk patients. Our study also highlights the need for continued close collaboration by acute care and community mental health providers for quality improvement