Search results for "NET"

Scleral Buckling: A Review of Clinical Aspects and Current Concepts

2021

Scleral buckling represents a valuable treatment option for rhegmatogenous retinal detachment repair. The surgery is based on two main principles: the closure of retinal breaks and the creation of a long-lasting chorioretinal adhesion. Buckles are placed onto the sclera with the purpose of sealing retinal breaks. Cryopexy is usually performed to ensure a long-lasting chorioretinal adhesion. Clinical outcomes of scleral buckling have been shown to be more favorable in phakic eyes with uncomplicated or medium complexity retinal detachment, yielding better anatomical and functional results compared with vitrectomy. Several complications have been described following scleral buckling surgery, s…

Viulunsoiton liikkeiden oppiminen Ivan Galamianin viulunsoiton ja -opetuksen menetelmässä : vertailu ja arviointi motoristen taitojen oppimisen teori…

1997

Procedures for study of teaching practices. Literature Review

2012

Interest in studying teaching practices has increased, because of the need to evaluate teachers and dissatisfaction with the usual ways of doing it. Recent approaches with Value-Added Models, based on students’ results on achievement tests do not seem satisfactory. The article is based on a review of literature and classifies the approaches to practices in three groups: instruments based on information given by teachers; observation protocols; and approaches based on the analysis of products of the practices. Specific tools are described and advantages and disadvantages of the three approaches are discussed. El interés por las prácticas docentes ha aumentado, en parte por la necesidad de ev…

Word Formation on Internet Gaming Forums

2008

HUMANISTINEN TIEDEKUNTA KIELTEN LAITOS Juhamatti Kalima WORD FORMATION ON INTERNET GAMING FORUMS Proseminaarityö Englannin kieli Toukokuu 2007 16 sivua + 1 liite Vaikka Internetistä eri muodoissaan on tulossa entistä suurempi osa jokapäiväistä kielenkäyttöä ja netissä syntyvät sanat siirtyvät myös suulliseen kielenkäyttöön, ei vakavaa tutkimusta Internetissä tapahtuvaan uusien sanojen sananmuodostukseen suoriteta läheskään tarpeeksi. Tämän proseminaarityön tarkoituksena olikin selvittää, mitkä sananmuodostusprosessit ovat yleisimpiä muodostettaessa uusia sanoja Internetin keskustelupalstoilla. Sananmuodostusprosessit ovat erilaisia prosesseja, joiden kautta kieleen muodostuu uusia sanoja. K…

Gas Emissions From the Western Aleutians Volcanic Arc

2021

The Aleutian Arc is remote and highly active volcanically. Its 4,000 km extent from mainland Alaska to Russia’s Kamchatka peninsula hosts over 140 volcanic centers of which about 50 have erupted in historic times. We present data of volcanic gas samples and gas emission measurements obtained during an expedition to the western-most segment of the arc in September 2015 in order to extend the sparse knowledge on volatile emissions from this remote but volcanically active region. Some of the volcanoes investigated here have not been sampled for gases before this writing. Our data show that all volcanoes host high-temperature magmatic-hydrothermal systems and have gas discharges typical of volc…

A Low-Cost Smartphone Sensor-Based UV Camera for Volcanic SO2 Emission Measurements

2017

Recently, we reported on the development of low-cost ultraviolet (UV) cameras, based on the modification of sensors designed for the smartphone market. These units are built around modified Raspberry Pi cameras (PiCams; ≈USD 25), and usable system sensitivity was demonstrated in the UVA and UVB spectral regions, of relevance to a number of application areas. Here, we report on the first deployment of PiCam devices in one such field: UV remote sensing of sulphur dioxide emissions from volcanoes; such data provide important insights into magmatic processes and are applied in hazard assessments. In particular, we report on field trials on Mt. Etna, where the utility of these devices in quantif…

A model of degassing for Stromboli volcano

2010

International audience; A better understanding of degassing processes at open-vent basaltic volcanoes requires collection of new datasets of H2O–CO2–SO2 volcanic gas plume compositions, which acquisition has long been hampered by technical limitations. Here, we use the MultiGAS technique to provide the best-documented record of gas plume discharges from Stromboli volcano to date. We show that Stromboli's gases are dominated by H2O (48–98 mol%; mean, 80%), and by CO2 (2–50 mol%; mean, 17%) and SO2 (0.2–14 mol%; mean, 3%). The significant temporal variability in our dataset reflects the dynamic nature of degassing process during Strombolian activity; which we explore by interpreting our gas m…

Spatially resolved SO2 flux emissions from Mt Etna

2016

Abstract We report on a systematic record of SO2 flux emissions from individual vents of Etna volcano (Sicily), which we obtained using a permanent UV camera network. Observations were carried out in summer 2014, a period encompassing two eruptive episodes of the New South East Crater (NSEC) and a fissure‐fed eruption in the upper Valle del Bove. We demonstrate that our vent‐resolved SO2 flux time series allow capturing shifts in activity from one vent to another and contribute to our understanding of Etna's shallow plumbing system structure. We find that the fissure eruption contributed ~50,000 t of SO2 or ~30% of the SO2 emitted by the volcano during the 5 July to 10 August eruptive inter…

Sulfur Degassing From Steam-Heated Crater Lakes: El Chichón (Chiapas, Mexico) and Víti (Iceland)

2018

The composition of the gases released by El Chichón (Chiapas, Mexico) and Víti (Askja volcano, Iceland) volcanic lakes is examined by Multi-GAS for the first time. Our results demonstrate that H2S and SO2 are degassed by these pH 2–3 lakes. We find higher CO2/H2S and H2/H2S ratios in the lakes' emissions (31–5,685 and 0.6–35, respectively) than in the fumarolic gases feeding the lakes (13–33 and 0.08–0.5, respectively), evidencing that only a fraction (0.2–5.4% at El Chichón) of the H2S(g) contributed by the subaquatic fumaroles ultimately reaches the atmosphere. At El Chichón, we estimate a H2S output from the crater lake of 0.02–0.06 t/day. Curiously, SO2 is also detected at trace levels …

Lidar detection of carbon dioxide in volcanic plumes

2015

Volcanic gases give information on magmatic processes. In particular, anomalous releases of carbon dioxide precede volcanic eruptions. Up to now, this gas has been measured in volcanic plumes with conventional measurements that imply the severe risks of local sampling and can last many hours. For these reasons and for the great advantages of laser sensing, the thorough development of volcanic lidar has been undertaken at the Diagnostics and Metrology Laboratory (UTAPRAD-DIM) of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA). In fact, lidar profiling allows one to scan remotely volcanic plumes in a fast and continuous way, and with high s…