Pulse Pressure Variation-Guided Fluid Therapy during Supratentorial Brain Tumour Excision: A Randomized Controlled Trial

BACKGROUND: Goal-directed fluid therapy (GDFT) improved patient outcomes in various surgical procedures; however, its role during mass brain resection was not well investigated. AIM: In this study, we evaluated a simple protocol based on intermittent evaluation of pulse pressure variation for guiding fluid therapy during brain tumour resection. METHODS: Sixty-one adult patients scheduled for supratentorial brain mass excision were randomized into either GDFT group (received intraoperative fluids guided by pulse pressure variation) and control group (received standard care). Both groups were compared according to the following: brain relaxation scale (BRS), mean arterial pressure, heart rate, urine output, intraoperative fluid intake, postoperative serum lactate, and length of hospital stay. RESULTS: Demographic data, cardiovascular data (mean arterial pressure and heart rate), and BRS were comparable between both groups. GDFT group received more intraoperative fluids {3155 (452) mL vs 2790 (443) mL, P = 0.002}, had higher urine output {2019 (449) mL vs 1410 (382) mL, P < 0.001}, and had lower serum lactate {0.9 (1) mmol versus 2.5 (1.1) mmol, P = 0.03} compared to control group. CONCLUSION: In conclusion, PPV-guided fluid therapy during supratentorial mass excision, increased intraoperative fluids, and improved peripheral perfusion without increasing brain swelling

Solar Activity Monitoring of Flares and CMEs Precursors through Lyman-Alpha Imaging and Tracking of Filaments and Prominences

International audienceWe investigate the advantages of imaging solar filaments and prominences in Lyman-Alpha, coupled to H-Alpha on ground, to develop more reliable precursors indicators for large flares, several hours before their occurrence

Solar Activity Monitoring of Flares and CMEs Precursors: the Importance of Lyman-Alpha

International audienceEvents preceding the onset of a are are called 'precursors', and one of the prominent precursors is a newly emerging bipolar region at the surface, which may interact with pre-existing magnetic field in the corona and trigger a flare. Another well-known precursor is the activation, or eruption, of a filament that is composed of relatively cool plasma (around 10000 K), oated in the hot coronal plasma. Both emerging regions and filaments are well observed in Lyman-Alpha and H-Alpha and we expect that their combination might lead to a better identification of the changes at the origin of major flares and CMEs. The objective of the study we present, carried with the LYRA/PROBA-2 instrument (observations of early 2010) and H-Alpha observations (Hida Observatory), is to monitor flares in Lyman-Alpha and to compare sensitivity difference with H-Alpha to develop better precursor indicators on the flaring region. Comparison is also made with classical EUV { X-ray indicators (GOES 1-8 A but also LYRA channels 2- 3, Aluminum 17{80 nm, and 2-4, Zirconium 6{20 nm), showing that Lyman-Alpha flares are equally sensitive and detectable, with the advantage, though, of providing significant precursors. H-Alpha - although 1000 times less intense as a flare than Lyman-Alpha (exemple of C9.9 February 2010 are presented) - is indicative of the precursor elements to study. Many H- Alpha observations sources are available but we preferably use Peru or Hida Observatory data when available since providing velocities (spectroheliograms). This Lyman-Alpha flares and precursors study is pursued with recent observations campaigns with a spare Lyman detector of LYRA. But this interesting possibility to open and watch for flares from a promising region implies, accordingly, to rely on good precursors indications to limit filter's degradation. These observations are pointing the interest for future Lyman-Alpha irradiance measurements coupled, for precursors identification, to solar disk imaging

Statistical Study of Confined Filament/Prominence Eruptions during Solar Cycle 23

International audienceFilament/prominence eruptions can have a significant impact on Earth's upper atmosphere and space environment, and are the primary drivers of what is now called space weather. To distinguish the different types of filament eruptions we statistically examine them during the 23rd Solar cycle. In this study we use 159 filament eruptions using the List of interplanetary (IP) Shocks Observed during Solar Cycle 23 (May 1996-January 2008) and their Source Information Environmental Satellites (GOES) X-ray plots (see Gopalswamy et al. [ 15 ]). It is found that 69% of the filament eruptions are confined eruptions, while 31% are ejective eruptions. Confined eruptions are 110 and 34 events (21%). They are due to active filaments and 76 events (48%) are due to disappearing filaments. The occurrences of active and disappearing filaments during the increasing phase of solar cycle 23 is found to be 80% while in the decreasing phase they are 13%. We have found that the dominant X-ray flare energy of confined eruptions is that of C class. The most common filaments field extent is located between 5 and 15 degrees. The most common flare duration is between 16 and 40 minutes

The Space Weather & Ultraviolet Solar Variability Microsatellite Mission (SWUSV)

International audienceWe present a summary of the scientific objectives, payload and mission profile of the Space Weather & Ultraviolet Solar Variability Microsatellite Mission (SWUSV) proposed to CNES and ESA (small mission)

The Space Weather and Ultraviolet Solar Variability (SWUSV) Microsatellite Mission

International audienceWe present the ambitions of the SWUSV (Space Weather and Ultraviolet Solar Variability) Microsatellite Mission that encompasses three major scientific objectives: (1) Space Weather including the prediction and detection of major eruptions and coronal mass ejections (Lyman-Alpha and Herzberg continuum imaging); (2) solar forcing on the climate through radiation and their interactions with the local stratosphere (UV spectral irradiance from 180 to 400 nm by bands of 20 nm, plus Lyman-Alpha and the CN bandhead); (3) simultaneous radiative budget of the Earth, UV to IR, with an accuracy better than 1% in differential. The paper briefly outlines the mission and describes the five proposed instruments of the model payload: SUAVE (Solar Ultraviolet Advanced Variability Experiment), an optimized telescope for FUV (Lyman-Alpha) and MUV (200-220 nm Herzberg continuum) imaging (sources of variability); UPR (Ultraviolet Passband Radiometers), with 64 UV filter radiometers; a vector magnetometer; thermal plasma measurements and Langmuir probes; and a total and spectral solar irradiance and Earth radiative budget ensemble (SERB, Solar irradiance & Earth Radiative Budget). SWUSV is proposed as a small mission to CNES and to ESA for a possible flight as early as 2017-2018