227 research outputs found
The 4.8 GHz LHC Schottky Pick-up System
The LHC Schottky observation system is based on traveling wave type high sensitivity pickup structures operating at 4.8 GHz. The choice of the structure and operating frequency is driven by the demanding LHC impedance requirements, where very low impedance is required below 2 GHz, and good sensitivity at the selected band at 4.8 GHz. A sophisticated filtering and triple down-mixing signal processing chain has been designed and implemented in order to achieve the specified 100 dB instantaneous dynamic range without range switching. Detailed design aspects for the complete systems and test results without beam are presented and discussed
Upper atmospheres and ionospheres of planets and satellites
The upper atmospheres of the planets and their satellites are more directly
exposed to sunlight and solar wind particles than the surface or the deeper
atmospheric layers. At the altitudes where the associated energy is deposited,
the atmospheres may become ionized and are referred to as ionospheres. The
details of the photon and particle interactions with the upper atmosphere
depend strongly on whether the object has anintrinsic magnetic field that may
channel the precipitating particles into the atmosphere or drive the
atmospheric gas out to space. Important implications of these interactions
include atmospheric loss over diverse timescales, photochemistry and the
formation of aerosols, which affect the evolution, composition and remote
sensing of the planets (satellites). The upper atmosphere connects the planet
(satellite) bulk composition to the near-planet (-satellite) environment.
Understanding the relevant physics and chemistry provides insight to the past
and future conditions of these objects, which is critical for understanding
their evolution. This chapter introduces the basic concepts of upper
atmospheres and ionospheres in our solar system, and discusses aspects of their
neutral and ion composition, wind dynamics and energy budget. This knowledge is
key to putting in context the observations of upper atmospheres and haze on
exoplanets, and to devise a theory that explains exoplanet demographics.Comment: Invited Revie
Titan's cold case files - Outstanding questions after Cassini-Huygens
The entry of the Cassini-Huygens spacecraft into orbit around Saturn in July 2004 marked the start of a golden era in the exploration of Titan, Saturn's giant moon. During the Prime Mission (2004â2008), ground-breaking discoveries were made by the Cassini orbiter including the equatorial dune fields (flyby T3, 2005), northern lakes and seas (T16, 2006), and the large positive and negative ions (T16 & T18, 2006), to name a few. In 2005 the Huygens probe descended through Titan's atmosphere, taking the first close-up pictures of the surface, including large networks of dendritic channels leading to a dried-up seabed, and also obtaining detailed profiles of temperature and gas composition during the atmospheric descent. The discoveries continued through the Equinox Mission (2008â2010) and Solstice Mission (2010â2017) totaling 127 targeted flybys of Titan in all. Now at the end of the mission, we are able to look back on the high-level scientific questions from the start of the mission, and assess the progress that has been made towards answering these. At the same time, new scientific questions regarding Titan have emerged from the discoveries that have been made. In this paper we review a cross-section of important scientific questions that remain partially or completely unanswered, ranging from Titan's deep interior to the exosphere. Our intention is to help formulate the science goals for the next generation of planetary missions to Titan, and to stimulate new experimental, observational and theoretical investigations in the interim
The Preparation of the Cryomagnets and the Assembly of the LHC Test String 2
The numerous complex activities required to prepare the cryomagnets for the installation in String 2 are described. These include the configuration of the mechanical interfaces, thee conditioning of the beam tubes, the installation of beam screens and the instrumentation as well as the final checks. The preparation of the cryomagnets for String 2 has been a dress rehearsal for the preparation that the cryomagnets will undergo before their installation in the tunnel. After a description of the interconnection procedures of the components for String 2, the tests carried-out to release the String for operation are described. A brief account of the lessons learnt is also given
A Pilot Study on Developing Mucosal Vaccine against Alveolar Echinococcosis (AE) Using Recombinant Tetraspanin 3: Vaccine Efficacy and Immunology
Humans and rodents become infected with E. multilocularis by oral ingesting of the eggs, which then develop into cysts in the liver and progress an endless proliferation. Untreated AE has a fatality rate of >90% in humans. Tetraspanins have been identified in Schistosoma and showed potential as the prospective vaccine candidates. In our recent study, we first identified seven tetraspanins in E. multilocularis and evaluated their protective efficacies as vaccines against AE when subcutaneously administered to BALB/c mice. Mucosal immunization of protective proteins is able to induce strong local and systemic immune responses, which might play a crucial role in protecting humans against E. multilocularis infection via the intestine, blood and liver. We focused on Em-TSP3, which achieved significant vaccine efficacy via both s.c. and i.n. routes. The adjuvanticity of nontoxic CpG OND as i.n. vaccine adjuvant was evaluated. The widespread expression of Em-TSP3 in all the developmental stages of E. multilocularis, and the strong local and systemic immune responses evoked by i.n. administration of rEm-TSP3 with CpG OND adjuvant suggest that this study might open the way for developing efficient, nontoxic human mucosal vaccines against AE
Titan's cold case files - Outstanding questions after Cassini-Huygens
Abstract The entry of the Cassini-Huygens spacecraft into orbit around Saturn in July 2004 marked the start of a golden era in the exploration of Titan, Saturn's giant moon. During the Prime Mission (2004â2008), ground-breaking discoveries were made by the Cassini orbiter including the equatorial dune fields (flyby T3, 2005), northern lakes and seas (T16, 2006), and the large positive and negative ions (T16 & T18, 2006), to name a few. In 2005 the Huygens probe descended through Titan's atmosphere, taking the first close-up pictures of the surface, including large networks of dendritic channels leading to a dried-up seabed, and also obtaining detailed profiles of temperature and gas composition during the atmospheric descent. The discoveries continued through the Equinox Mission (2008â2010) and Solstice Mission (2010â2017) totaling 127 targeted flybys of Titan in all. Now at the end of the mission, we are able to look back on the high-level scientific questions from the start of the mission, and assess the progress that has been made towards answering these. At the same time, new scientific questions regarding Titan have emerged from the discoveries that have been made. In this paper we review a cross-section of important scientific questions that remain partially or completely unanswered, ranging from Titan's deep interior to the exosphere. Our intention is to help formulate the science goals for the next generation of planetary missions to Titan, and to stimulate new experimental, observational and theoretical investigations in the interim
Giant primary adrenal hydatid cyst presenting with arterial hypertension: a case report and review of the literature
<p>Abstract</p> <p>Introduction</p> <p>A primary hydatid cyst of the adrenal gland is still an exceptional localization. The adrenal gland is an uncommon site even in Morocco, where echinococcal disease is endemic.</p> <p>Case presentation</p> <p>We report the case of a 64-year-old Moroccan man who presented with the unusual symptom of arterial hypertension associated with left flank pain. Computed tomography showed a cystic mass of his left adrenal gland with daughter cysts filing the lesion (Type III). Despite his negative serology tests, the diagnosis of a hydatid cyst was confirmed on surgical examination. Our patient underwent surgical excision of his left adrenal gland with normalization of blood pressure. No recurrence has occurred after 36 months of follow-up.</p> <p>Conclusion</p> <p>There are two remarkable characteristics of this case report; the first is the unusual location of the cyst, the second is the association of an adrenal hydatid cyst with arterial hypertension, which has rarely been reported in the literature.</p
Effects of Saturn's magnetospheric dynamics on Titan's ionosphere
We use the Cassini Radio and Plasma Wave Science/Langmuir probe measurements of the electron density from the first 110 flybys of Titan to study how SaturnÂŽs magnetosphere influences TitanÂŽs ionosphere. The data is first corrected for biased sampling due to varying solar zenith angle and solar energy flux (solar cycle effects). We then present results showing that the electron density in TitanÂŽs ionosphere, in the altitude range 1600-2400 km, is increased by about a factor of 2.5 when Titan is located on the nightside of Saturn (Saturn local time (SLT) 21-03 h) compared to when on the dayside (SLT 09-15 h). For lower altitudes (1100-1600 km) the main dividing factor for the ionospheric density is the ambient magnetospheric conditions. When Titan is located in the magnetospheric current sheet, the electron density in TitanÂŽs ionosphere is about a factor of 1.4 higher compared to when Titan is located in the magnetospheric lobes. The factor of 1.4 increase in between sheet and lobe flybys is interpreted as an effect of increased particle impact ionization from 200 eV sheet electrons. The factor of 2.5 increase in electron density between flybys on SaturnÂŽs nightside and dayside is suggested to be an effect of the pressure balance between thermal plus magnetic pressure in TitanÂŽs ionosphere against the dynamic pressure and energetic particle pressure in SaturnÂŽs magnetosphere.Fil: Edberg, N. J. T.. University of Iowa; Estados Unidos. Swedish Institute of Space Physics; SueciaFil: Andrews, D. J.. Swedish Institute of Space Physics; SueciaFil: Bertucci, Cesar. Consejo Nacional de InvestigaciĂłnes CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de AstronomĂa y FĂsica del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de AstronomĂa y FĂsica del Espacio; ArgentinaFil: Gurnett, D. A.. University of Iowa; Estados UnidosFil: Holmberg, M. K. G.. Swedish Institute of Space Physics; SueciaFil: Jackman, C. M.. University Of Southampton; Reino UnidoFil: Kurth, W. S.. University of Iowa; Estados UnidosFil: Menietti, J. D.. University Of Iowa; Estados UnidosFil: Opgenoorth, H. J.. Swedish Institute of Space Physics; SueciaFil: Shebanits, O.. Swedish Institute of Space Physics; SueciaFil: Vigren, E.. Swedish Institute of Space Physics; SueciaFil: Wahlund, J. E.. Swedish Institute of Space Physics; Sueci
Hydatid cyst fluid promotes peri-cystic fibrosis in cystic echinococcosis by suppressing miR-19 expression
Justified Concern or Exaggerated Fear: The Risk of Anaphylaxis in Percutaneous Treatment of Cystic EchinococcosisâA Systematic Literature Review
Percutaneous treatment (PT) emerged in the mid-1980s as an alternative to surgery for selected cases of abdominal cystic echinococcosis (CE). Despite its efficacy and widespread use, the puncture of echinococcal cysts is still far from being universally accepted. One of the main reasons for this reluctance is the perceived risk of anaphylaxis linked to PTs. To quantify the risk of anaphylactic reactions and lethal anaphylaxis with PT, we systematically searched MEDLINE for publications on PT of CE and reviewed the PT-related complications. After including 124 publications published between 1980 and 2010, we collected a total number of 5943 PT procedures on 5517 hepatic and non-hepatic echinococcal cysts. Overall, two cases of lethal anaphylaxis and 99 reversible anaphylactic reactions were reported. Lethal anaphylaxis occurred in 0.03% of PT procedures, corresponding to 0.04% of treated cysts, while reversible allergic reactions complicated 1.7% of PTs, corresponding to 1.8% of treated echinococcal cysts. Analysis of the literature shows that lethal anaphylaxis related to percutaneous treatment of CE is an extremely rare event and is observed no more frequently than drug-related anaphylactic side effects
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