23 research outputs found
WITHDRAWN: Experimental evidence of the wind-induced bias of precipitation gauges using Particle Image Velocimetry and particle tracking in the wind tunnel
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Wind-tunnel measurements of the airflow pattern above the collector of different shielded and unshielded precipitation gauges.
Wind is the first environmental source of precipitation undercatch for catching-type precipitation gauge. This
work presents an aerodynamic investigation on different precipitation gauge geometries and on a wind shield
by means of wind tunnel tests. Experiments have been jointly performed by University of Genoa, DICCA, and
Politecnico di Milano within the Italian project PRIN 20154WX5NA \u201cReconciling precipitation with runoff: the
role of understated measurement biases in the modelling of hydrological processes\u201d.
The airflow, around precipitation gauges, was measured employing two different experimental techniques:
a traversing system equipped with \u201cCobra\u201d multi hole pressure probes and the Particles Image Velocimetry PIV.
Cobra probes allow to measure the three components of the local flow velocity in the measuring points, while PIV
technique provides two-dimensional velocity fields on the investigated planes.
The airflow velocity and direction were investigated for different wind speed values and different precipitation
gauge geometries: the \u201cchimney\u201d, the \u201ccylindrical\u201d and the \u201cinverted conical\u201d shapes. The effect of a traditional
Single Alter windshield was also assessed on the cylindrical shape.
These experiments allow to detect qualitatively and quantitatively the main features of the flow, speed-up and
updraft, above the collector which influence the particle trajectories and their collection. Results confirm the
dependency of the airflow disturbance on the gauge geometry, especially in terms of maximum local velocity
and distribution of the upward and downward components of the vertical velocity. PIV velocity fields and Cobra
velocity profiles show the expected attenuation of the flow velocity above a gauge located inside the windshield
due to the break of the flow induced by the shield slats.
The experimental campaign provided a wide dataset suitable for the validation of numerical Computational
Fluid Dynamics simulations. This work is propaedeutic to the quantification of the precipitation undercatch and
the elaboration of correction curves to obtain the actual precipitation in windy conditions
The Italian National Strategy for Sustainable Development and the Covid-19 impact: a regional analysis
The Italian National Strategy for Sustainable Development plays an important role in the national implementation of the 17 Goals for sustainable development set globally through the 2030 Agenda of the United Nations. The achievement of such goals in Italy is linked to the strategic choices and objectives established at the national level. The purpose of this work is to monitor the performance of the 20 Italian regions in 4 of the 5 areas of the Agenda (People, Planet, Prosperity, Peace) over a period of time ranging from the implementation of the National Strategy to the post-pandemic. To do this, a set of representative indicators was created and a geographical sustainability assessment tool (SSAM) was used, which operates through a multicriteria analysis model perfectly integrated into a GIS environment. The results showed a strong regional variability and a radicalized North-South gap. Moreover, the monitoring between the different years (2017-2019-2021) showed the initially positive impact of the strategy, mainly due to the Planet dimension, but also the negative one that COVID-19 caused to all the regions, with different intensity depending on the dimensions considered
A actividade viral do xeo mariño da Antártida aumenta a aerosolización primaria
Trabajo final presentado por Arianna Rocchi para el Máster Interuniversitario en Biología Marina de la Universidade da Coruña (UDC), realizado bajo la dirección del Dr. Manuel Dall'Osto y de la Dra. Dolors Vaqué Vidal del Institut de Ciències del Mar (ICM-CSIC).-- 37 pages, 19 figures, 1 table[EN] The ocean covers 71% of the surface of our planet Earth and viruses are extremely abundant. Marine viruses play a key role in modulating several biogeochemical cycles. Still - very little is known about their role in the production of aerosol, clouds and climate change.
A recent interest on the marine viruses' contribution to the marine aerosols is growing, revealing that - after viral infection - phytoplankton (nanoflagellates) and prokaryote (bacteria) cells release organic matter to the water. The new released organic matter can contribute at making primary marine aerosol - produced at the sea surface through interaction between wind and waves, and subsequent bubble bursting. Aerosol particles affect the hydrological cycle because they act as cloud condensation nuclei (CCN) thereby influencing the formation and development of clouds.
Therefore, the aim of this thesis is to test if the lysis of prokaryotes (bacteria) and eukaryotes (heterotrophic and phototrophic nanoflagellates) - produced by viruses in melted sea ice - affects the production of primary organic marine aerosols. To achieve this goal, we carried out melted sea ice - atmosphere experiments in a marine controlled and bubble-bursting aerosol generation chamber in the laboratory during the Spanish 2018-2019 Antarctic campaign. This thesis is presented into two main sections: 1) results produced in this thesis (mortality experiments and biological measurements) and 2) results discussed with complementary data produced by other colleagues.
Preliminary results are promising, showing an increase in viral abundance and production, rate of lysed prokaryotes and eukaryotes and the organic carbon released from these lysed cells when viral concentrate is added, followed by a rise in the number of atmospheric aerosols produced within primary aerosol chamber. In a nutshell, this study points to the direction on which the fresh organic matter released in the water from melted sea ice is an important source of Antarctic marine aerosols[ES] El océano cubre el 71% de la superficie de nuestro planeta Tierra y los virus son extremadamente abundantes (10 30). Los virus marinos desempeñan un papel clave en la modulación de varios ciclos biogeoquímicos, todavía se sabe muy poco sobre su papel en la producción de aerosoles, nubes y cambio climático.
Un interés reciente en la contribución de los virus marinos a los aerosoles marinos está creciendo, revelando que - después de la infección viral - fitoplancton (nanoflagelados) y células procariotas (bacterias) liberan materia orgánica al agua. La nueva materia orgánica liberada puede contribuir a la producción de aerosol marino primario - producido en la superficie del mar a través de la interacción entre el viento y las olas, y posterior formación de burbujas. Las partículas de aerosol afectan al ciclo hidrológico porque actúan como núcleos de condensación de nubes (CCN).
Por lo tanto, el objetivo de mi tesis es probar si la lisis de procariotas (bacterias) y eucariotas (nanoflagelados heterotróficos y fototróficos) - producida por infección viral en el hielo marino derretido - afecta la producción de aerosoles marinos orgánicos primarios. Para lograr este objetivo, realizamos experimentos de hielo marino fundido - atmósfera en un tanque de generación de aerosoles en laboratorio durante la campaña española 2018-2019 en la Antártida.
Esta tesis se presenta en dos secciones principales: 1) resultados producidos en esta tesis (experimentos de mortalidad y mediciones biológicas) y 2) resultados discutidos con datos complementarios producidos por otros colegas.
Los resultados preliminares son prometedores, mostrando un aumento en la abundancia y producción viral, la tasa de procariotas y eucariotas lisadas y el carbono orgánico liberado de estas células lisadas cuando se añade el concentrado viral, seguido de un aumento del número de partículas de aerosol producidas en el tanque empleado para para la realización de los experimentos con muestras de hielo. En pocas palabras, este estudio confirma como la materia orgánica liberada del hielo marino derretido a la columna de agua es una fuente importante de aerosolesPeer reviewe
Investigadores españoles zarpan al Ártico para estudiar la formación de nubes
Investigadores del Instituto de Ciencias del Mar (ICM-CSIC) zarparán el próximo jueves en el buque oceanográfico Akademik Tryoshnikov desde el puerto de Murmansk (Rusia) para estudiar zonas poco accesibles y remotas en los mares de Kara y Laptev, así como en la Tierra de Francisco José y Severnaya Zemlya, ubicadas en el Ártico occidentalPeer reviewe
Toward dosing precision and insulin stability in an artificial pancreas system
A fully implantable artificial pancreas (AP) still represents the holy grail for diabetes treatment. The quest for efficient miniaturized implantable insulin pumps, able to accurately regulate the blood glucose profile and to keep insulin stability, is still persistent. This work describes the design and testing of a microinjection system connected to a variable volume insulin reservoir devised to favor insulin stability during storage. The design, the constitutive materials, and the related fabrication techniques were selected to favor insulin stability by avoiding-or at least limiting-hormone aggregation. We compared substrates made of nylon 6 and Teflon, provided with different surface roughness values due to the employed fabrication procedures (i.e., standard machining and spray deposition). Insulin stability was tested in a worst case condition for 14 days, and pumping system reliability and repeatability in dosing were tested over an entire reservoir emptying cycle. We found that nylon 6 guarantees a higher insulin stability than Teflon and that independent of the material used, larger roughness determines a higher amount of insulin aggregates. A dedicated rotary pump featured by a 1-lL delivery resolution was developed and connected through a proper gear mechanism to a variable volume air-tight insulin reservoir. The microinjection system was also able to operate in a reverse mode to enable the refilling of the implanted reservoir. The developed system represents a fundamental building block toward the development of a fully implantable AP and could be advantageously integrated even in different implantable drug delivery apparatus (e.g., for pain management)
Wind tunnel tests to evaluate the rain drops deviations around different types of precipitation gauges
Wind tunnel validation of a particle tracking model to assess the wind-induced undercatch of rainfall gauges
Trauma-Associated Pulmonary Laceration in Dogs—A Cross Sectional Study of 364 Dogs
In this study, we describe the computed tomography (CT) features of pulmonary laceration in a study population, which included 364 client-owned dogs that underwent CT examination for thoracic trauma, and compared the characteristics and outcomes of dogs with and without CT evidence of pulmonary laceration. Lung laceration occurred in 46/364 dogs with thoracic trauma (prevalence 12.6%). Dogs with lung laceration were significantly younger than dogs in the control group (median 42 months (interquartile range (IQR) 52.3) and 62 months (IQR 86.1), respectively; p = 0.02). Dogs with lung laceration were significantly heavier than dogs without laceration (median 20.8 kg (IQR 23.3) and median 8.7 kg (IQR 12.4 kg), respectively p < 0.0001). When comparing groups of dogs with thoracic trauma with and without lung laceration, the frequency of high-energy motor vehicle accident trauma was more elevated in dogs with lung laceration than in the control group. No significant differences were observed between groups regarding tge frequency and length of hospitalization and 30-day mortality. Similar to the human classification scheme, four CT patterns are described in dogs in this study: Type 1, large pulmonary laceration located deeply in the pulmonary parenchyma or around an interlobar fissure; Type 2, laceration occurring in the paraspinal lung parenchyma, not associated with vertebral fracture; Type 3, subpleural lung laceration intimately associated with an adjacent rib or vertebral fracture; Type 4, subpleural lesions not associated with rib fractures. Complications were seen in 2/46 dogs and included lung abscess and collapse