Multi-wavelength observations of planet forming disks: Constraints on planet formation processes

Our understanding of protoplanetary disks has greatly improved over the last decade due to a wealth of data from new facilities. Unbiased dust surveys with Spitzer leave us with good constraints on the dust dispersal timescale of small grains in the terrestrial planet forming region. In the ALMA era, this can be confronted for the first time also with evolutionary timescales of mm grains in the outer disk. Gas surveys in the context of the existing multi-wavelength dust surveys will be a key in large statistical studies of disk gas evolution. Unbiased gas surveys are limited to ALMA CO submm surveys, where the quantitative interpretation is still debated. Herschel gas surveys have been largely biased, but [OI] 63 mic surveys and also accretion tracers agree qualitatively with the evolutionary timescale of small grains in the inner disk. Recent advances achieved by means of consistent multi-wavelength studies of gas AND dust in planet forming disks reveal the subtleties of the quantitative interpretation of gas surveys. Observational methods to determine disk masses e.g. from CO submm lines require the knowledge of the dust properties in the disk. Understanding not only the gas evolution, but also its chemical composition will provide crucial input for planet formation models. Kinetic chemical results give profoundly different answers than thermodynamic equilibrium in terms of the C/O ratios as well as the water ice/rock ratios. Again, dust has a key impact on the chemical evolution and composition of the gas. Grain growth for example affects freeze-out processes and strongly increases the cosmic ray induced UV field.Comment: appears in the proceedings of the conference "The Cosmic Wheel and the Legacy of the AKARI archive: from galaxies and stars to planets and life", October 17-20, 2017, Tokyo, Japa

Human chorionic gonadotropin-mediated induction of breast cancer cell proliferation and differentiation

Human chorionic gonadotropin (hCG) is a hormone that specifically binds to luteinizing hormone receptor (LHR) and exerts several roles, including the support of pregnancy and fetal gonadal steroidogenesis. Since hCG is also expressed by some tumor types, like breast cancer, many efforts have been made to study its role in neoplesia, with some studies showing a cancer-supportive role and others showing a cancer-protective role. A critical examination of the literature highlighted that the in vitro effect of hCG has been tested in the presence of fetal serum, which contains other gonadotropins, in the culture medium. Thus, we hypothesized that the use of serum in the cell culture medium might influence the cell response to the hCG treatment due to the presence of other hormones. Thus, we analyzed the in vitro effect of highly purified hCG on cell proliferation and the activation of the down-stream signal transduction pathway in three breast cancer cell lines, particularly focusing on MCF7, cultured in serum-deprived conditions. Our data show that hCG increases cell proliferation and activates the down-stream target Akt, together with a decrease of the LHR mRNA expression level. Finally, we also tested the differentiation capacity of hCG on MCF7 cancer stem cells (CSCs) and show that it favors the proliferation and differentiation of these cells, thus suggesting that hCG also renders cells more able to colonize and invade the organs

Divergent roles of mitochondria dynamics in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive tumors; it is often diagnosed at an advanced stage and is hardly treatable. These issues are strictly linked to the absence of early diagnostic markers and the low efficacy of treatment approaches. Recently, the study of the metabolic alterations in cancer cells has opened the way to important findings that can be exploited to generate new potential therapies. Within this scenario, mitochondria represent important organelles within which many essential functions are necessary for cell survival, including some key reactions involved in energy metabolism. These organelles remodel their shape by dividing or fusing themselves in response to cellular needs or stimuli. Interestingly, many authors have shown that mitochondrial dynamic equilibrium is altered in many different tumor types. However, up to now, it is not clear whether PDAC cells preferentially take advantage of fusion or fission processes since some studies reported a wide range of different results. This review described the role of both mitochondria arrangement processes, i.e., fusion and fission events, in PDAC, showing that a preference for mitochondria fragmentation could sustain tumor needs. In addition, we also highlight the importance of considering the metabolic arrangement and mitochondria assessment of cancer stem cells, which represent the most aggressive tumor cell type that has been shown to have distinctive metabolic features to that of differentiated tumor cells

Efficient Breast Cancer Classification Using Histopathological Images and a Simple VGG

Breast cancer is the second most deadly disease worldwide. This severe condition led to 627,000 people dying in 2018. Thus, early detection is critical for improving the patients' lifetime or even curing them. In this context, we can appeal to Medicine 4.0, which exploits machine learning capabilities to obtain a faster and more efficient diagnosis. Therefore, this work aims to apply a simpler convolutional neural network, called VGG-7, for classifying breast cancer in histopathological images. Results have shown that VGG-7 overcomes the performance of VGG-16 and VGG-19, showing an accuracy of 98%, a precision of 99%, a recall of 98%, and an F1 score of 98%

Observational studies of gas in protoplanetary disks

The gas dominates the mass and dynamics of protoplanetary disks.However, very few observational constraints exist about the physical properties of the gas in the planet forming region of the disks. This thesis presents an ensemble of new observational projects aimed at studying the gas in the disks of selected nearby Herbig Ae/Be stars (HAEBES) and classical T Tauri stars (CTTS). In the first chapter we present a search for CO 4.7 micron ro-vibrational emission from HAEBES using ISAAC, ESO's first generation VLT near-infrared spectrograph. In the second chapter, we describe a project in which we intended to probe the outer cold gas of protoplanetary disks, by measuring gas absorption features of the disk superimposed on the optical spectra of close (< 1.5") visual companions of nearby HAEBES utilizing FORS2, ESO's VLT optical spectrograph. In the third chapter, we present a large observational effort to detect H2 fundamental rotational emission at 12.278 and 17.035 $\mu$m from HAEBES employing VISIR, ESO's new high-resolution mid-infrared spectrograph. In the fourth chapter, we describe the first results of a sensitive search for near-infrared H2 ro-vibrational emission at 2.1218, 2.2233 and 2.2477 micron in the CTTS LkHa 264 and the debris disk 49 Cet using CRIRES, ESO's new VLT near-infrared high-resolution spectrograph. From our observations (detections and non-detections), we derive important constraints on the physical properties of the studied disks (e.g. mass, column density, temperature, age, excitation mechanism, inclination). We show that high-resolution infrared spectroscopy is a crucial tool for future studies of the structure of protoplanetary disks

PAH emission in the proplyd HST10: what is the mechanism behind photoevaporation?

Proplyds are photodissociation region (PDR)-like cometary cocoons around young stars which are thought to originate through photo-evaporation of the central protoplanetary disk by external UV radiation from the nearby OB stars. This letter presents spatially resolved mid-infrared imaging and spectroscopy of the proplyd HST10 obtained with the VLT/VISIR instrument. These observations allow us to detect Polycyclic Aromatic Hydrocarbons (PAH) emission in the proplyd photodissociation region and to study the general properties of PAHs in proplyds for the first time. We find that PAHs in HST10 are mostly neutral and at least 50 times less abundant than typical values found for the diffuse ISM or the nearby Orion Bar. With such a low PAH abundance, photoelectric heating is significantly reduced. If this low abundance pertains also to the original disk material, gas heating rates could be too low to efficiently drive photoevaporation unless other processes can be identified. Alternatively, the model behind the formation of proplyds as evaporating disks may have to be revised.Comment: 5 pages, 3 figures, 1 tabl

Creacion de una cooperativa recolectora de pollinaza en la vereda la comba del municipio de santo domingo, Antioquia

La empresa Operadora Avícola Colombia S.A.S tiene una Granja avícola de pollos de engorde de 100.000 aves, en una zona rural de la Vereda la Comba perteneciente al Municipio de Santo Domingo del departamento de Antioquia. La pollinaza, subproducto que resulta de la producción, es vendida en su totalidad a una empresa de Medellín, la cual lo procesa para luego venderlo a agropecuarias de diferentes municipios, entre ellos Santo Domingo. La empresa paga los servicios una cuadrilla a través de un contratista que se desplaza desde Medellín para la recolección de la pollinaza una vez después de evacuado el pollo para proceso. Los pequeños agricultores de la región tienen que adquirir este abono ya procesado a altos costos debido a los intermediarios, además del transporte hasta sus parcelas. Con este proyecto se pretende beneficiarlos con la propuesta de que sean ellos quienes conformen el grupo de recolección, y que puedan obtener el producto a más bajo precio, contribuyendo también a la reducción de costos a la empresa por la contratación de la cuadrilla y la agilidad de evacuación de la pollinaza por estar dentro de la misma vereda.The company Operadora Avícola Colombia S.A.S has a poultry farm for broiler chickens of 100,000 birds, in a rural area of ​​La Vereda Comba belonging to the Municipality of Santo Domingo in the department of Antioquia. The pollinaza, a byproduct resulting from the production, is sold in its entirety to a company in Medellín, which processes it and then sell it to farmers from different municipalities, including Santo Domingo. The company pays the services for a crew through a contractor that travels from Medellín for the collection of the chicken pole once after the chicken has been evacuated for processing. The small farmers of the region have to acquire this already processed fertilizer at high costs due to the intermediaries, in addition to the transport to their plots. This project aims to benefit them with the proposal that they are the ones who make up the collection group, and that they can obtain the product at a lower price, also contributing to the reduction of costs to the company due to the hiring of the crew and the agility of evacuation of the poultry car due to being inside the same path

IndicadoresWeb, un sistema de información para el seguimiento a la calidad de los procesos

Las instituciones prestadoras de servicios de salud, como la Clínica El Rosario, de forma periódica se enfrentan a procesos de auditorías externas por diferentes entes de vigilancia y control (Resolución 2003, 2014, artículo 5)1. Estas auditorías buscan velar por la calidad en la prestación de los servicios de salud y pueden implicar cierres de servicios o reconocimientos por una excelente gestión y resultados. Por esta razón, las instituciones prestadoras de servicio de salud se ven en la necesidad de desarrollar una cultura de mejoramiento continuo y constante monitoreo de sus resultados. La medición continua soporta la toma de decisiones, permite anteponerse a las evaluaciones de los entes de control y ayuda a la institución a posicionarse en un mercado competitivo y con mucha regulación, siendo los resultados de sus indicadores el factor diferenciador en el medio. En los procesos de vigilancia y control de las instituciones prestadoras de servicios de salud es de obligatorio cumplimiento la presentación de indicadores, lo cual permite corroborar la calidad en cada uno de los servicios (Resolución 2003, 2014, artículo 35-2)1. Por medio de los indicadores y su trazabilidad se evidencia el comportamiento de un proceso que hace parte del servicio, así como, soporta la calificación obtenida en un periodo determinado. Actualmente, la Clínica El Rosario no cuenta con un sistema de información capaz de realizar el seguimiento sistematizado a los procesos. La medición de indicadores se basa en un proceso manual en el cual la calidad de la información no es óptima.Por estas razones, la Clínica el Rosario aprueba el desarrollo de IndicadoresWeb, una herramienta propia con posibilidad de adaptación de la herramienta a conveniencia, de acuerdo a las necesidades institucionales, así como, cambios normativos. Se busca con este proyecto integrar todos los indicadores que se requieran medir por parte de la institución. La herramienta se desarrolló con tecnologías Microsoft (Visual Studio 2015 profesional y SQL server 2015). Para todo el proceso del desarrollo del software se empleó un modelamiento en espiral (Sommerville & Galipienso, 2005, numeral 4.2.2). En la toma de requerimientos se utilizaron técnicas de ingeniería y desarrollo de software avanzada como: lenguaje natural, diagrama de actores y diagramas de procesos. En la etapa del modelado de los formularios se emplearon diagramas UML y a nivel de bases de datos un modelado relacional de una base de datos transaccional.Ingeniero de Sistemaspregrad

Dust Traps in the Protoplanetary Disk MWC 758: Two Vortices Produced by Two Giant Planets?

Resolved ALMA and VLA observations indicate the existence of two dust traps in the protoplanetary disc MWC 758. By means of two-dimensional gas+dust hydrodynamical simulations post-processed with three-dimensional dust radiative transfer calculations, we show that the spirals in scattered light, the eccentric, asymmetric ring and the crescent-shaped structure in the (sub)millimetre can all be caused by two giant planets: a 1.5-Jupiter mass planet at 35 au (inside the spirals) and a 5-Jupiter mass planet at 140 au (outside the spirals). The outer planet forms a dust-trapping vortex at the inner edge of its gap (at ∼85 au), and the continuum emission of this dust trap reproduces the ALMA and VLA observations well. The outer planet triggers several spiral arms that are similar to those observed in polarized scattered light. The inner planet also forms a vortex at the outer edge of its gap (at ∼50 au), but it decays faster than the vortex induced by the outer planet, as a result of the disc’s turbulent viscosity. The vortex decay can explain the eccentric inner ring seen with ALMA as well as the low signal and larger azimuthal spread of this dust trap in VLA observations. Finding the thermal and kinematic signatures of both giant planets could verify the proposed scenario

Accretion process, magnetic fields, and apsidal motion in the pre-main sequence binary DQ Tau

Classical T Tauri stars (CTTSs) are young stellar objects that accrete materials from their accretion disc influenced by their strong magnetic field. The magnetic pressure truncates the disc at a few stellar radii and forces the material to leave the disc plane and fall onto the stellar surface by following the magnetic field lines. However, this global scheme may be disturbed by the presence of a companion interacting gravitationally with the accreting component. This work is aiming to study the accretion and the magnetic field of the tight eccentric binary DQ Tau, composed of two equal-mass ($\sim$ 0.6 \msun ) CTTSs interacting at different orbital phases. We investigated the variability of the system using a high-resolution spectroscopic and spectropolarimetric monitoring performed with ESPaDOnS at the CFHT. We provide the first ever magnetic field analysis of this system, the Zeeman-Doppler imaging revealed a stronger magnetic field for the secondary than the primary (1.2 kG and 0.5 kG, respectively), but the small-scale fields analysed through Zeeman intensification yielded similar strengths (about 2.5 kG). The magnetic field topology and strengths are compatible with the accretion processes on CTTSs. Both components of this system are accreting, with a change of the main accretor during the orbital motion. In addition, the system displays a strong enhancement of the mass accretion rate at periastron and apastron. We also discovered, for the first time in this system, the apsidal motion of the orbital ellipse.Comment: 18 pages, 20 figures. Accepted for publication in MNRA