1
|
The Comet Interceptor Mission. SPACE SCIENCE REVIEWS 2024; 220:9. [PMID: 38282745 PMCID: PMC10808369 DOI: 10.1007/s11214-023-01035-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/29/2023] [Indexed: 01/30/2024]
Abstract
Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA's F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum Δ V capability of 600 ms - 1 . Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes - B1, provided by the Japanese space agency, JAXA, and B2 - that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission's science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.
Collapse
|
2
|
Observations of a Solar Energetic Particle Event From Inside and Outside the Coma of Comet 67P. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2022; 127:e2022JA030398. [PMID: 37032655 PMCID: PMC10077910 DOI: 10.1029/2022ja030398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 08/07/2022] [Accepted: 09/29/2022] [Indexed: 06/19/2023]
Abstract
We analyze observations of a solar energetic particle (SEP) event at Rosetta's target comet 67P/Churyumov-Gerasimenko during 6-10 March 2015. The comet was 2.15 AU from the Sun, with the Rosetta spacecraft approximately 70 km from the nucleus placing it deep inside the comet's coma and allowing us to study its response. The Eastern flank of an interplanetary coronal mass ejection (ICME) also encountered Rosetta on 6 and 7 March. Rosetta Plasma Consortium data indicate increases in ionization rates, and cometary water group pickup ions exceeding 1 keV. Increased charge exchange reactions between solar wind ions and cometary neutrals also indicate increased upstream neutral populations consistent with enhanced SEP induced surface activity. In addition, the most intense parts of the event coincide with observations interpreted as an infant cometary bow shock, indicating that the SEPs may have enhanced the formation and/or intensified the observations. These solar transient events may also have pushed the cometopause closer to the nucleus. We track and discuss characteristics of the SEP event using remote observations by SOHO, WIND, and GOES at the Sun, in situ measurements at Solar Terrestrial Relations Observatory Ahead, Mars and Rosetta, and ENLIL modeling. Based on its relatively prolonged duration, gradual and anisotropic nature, and broad angular spread in the heliosphere, we determine the main particle acceleration source to be a distant ICME which emerged from the Sun on 6 March 2015 and was detected locally in the Martian ionosphere but was never encountered by 67P directly. The ICME's shock produced SEPs for several days which traveled to the in situ observation sites via magnetic field line connections.
Collapse
|
3
|
The Plasma Environment of Comet 67P/Churyumov-Gerasimenko. SPACE SCIENCE REVIEWS 2022; 218:65. [PMID: 36397966 PMCID: PMC9649581 DOI: 10.1007/s11214-022-00931-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 10/20/2022] [Indexed: 06/04/2023]
Abstract
The environment of a comet is a fascinating and unique laboratory to study plasma processes and the formation of structures such as shocks and discontinuities from electron scales to ion scales and above. The European Space Agency's Rosetta mission collected data for more than two years, from the rendezvous with comet 67P/Churyumov-Gerasimenko in August 2014 until the final touch-down of the spacecraft end of September 2016. This escort phase spanned a large arc of the comet's orbit around the Sun, including its perihelion and corresponding to heliocentric distances between 3.8 AU and 1.24 AU. The length of the active mission together with this span in heliocentric and cometocentric distances make the Rosetta data set unique and much richer than sets obtained with previous cometary probes. Here, we review the results from the Rosetta mission that pertain to the plasma environment. We detail all known sources and losses of the plasma and typical processes within it. The findings from in-situ plasma measurements are complemented by remote observations of emissions from the plasma. Overviews of the methods and instruments used in the study are given as well as a short review of the Rosetta mission. The long duration of the Rosetta mission provides the opportunity to better understand how the importance of these processes changes depending on parameters like the outgassing rate and the solar wind conditions. We discuss how the shape and existence of large scale structures depend on these parameters and how the plasma within different regions of the plasma environment can be characterised. We end with a non-exhaustive list of still open questions, as well as suggestions on how to answer them in the future.
Collapse
|
4
|
A Case for Electron-Astrophysics. EXPERIMENTAL ASTRONOMY 2021; 54:473-519. [PMID: 36915623 PMCID: PMC9998602 DOI: 10.1007/s10686-021-09761-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 05/07/2021] [Indexed: 06/18/2023]
Abstract
The smallest characteristic scales, at which electron dynamics determines the plasma behaviour, are the next frontier in space and astrophysical plasma research. The analysis of astrophysical processes at these scales lies at the heart of the research theme of electron-astrophysics. Electron scales are the ultimate bottleneck for dissipation of plasma turbulence, which is a fundamental process not understood in the electron-kinetic regime. In addition, plasma electrons often play an important role for the spatial transfer of thermal energy due to the high heat flux associated with their velocity distribution. The regulation of this electron heat flux is likewise not understood. By focussing on these and other fundamental electron processes, the research theme of electron-astrophysics links outstanding science questions of great importance to the fields of space physics, astrophysics, and laboratory plasma physics. In this White Paper, submitted to ESA in response to the Voyage 2050 call, we review a selection of these outstanding questions, discuss their importance, and present a roadmap for answering them through novel space-mission concepts.
Collapse
|
5
|
Inhibition de l’expression des GRK2/3 dans l’épiderme psoriasique. Ann Dermatol Venereol 2020. [DOI: 10.1016/j.annder.2020.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
6
|
History and Background of Progress toward Equal Footing with the Sighted. JOURNAL OF VISUAL IMPAIRMENT & BLINDNESS 2020. [DOI: 10.1177/0145482x5204600605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
7
|
230 Psoriatic epidermis is associated with upregulation of CDK2 and inhibition of CDK4 activity. J Invest Dermatol 2019. [DOI: 10.1016/j.jid.2019.07.231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
8
|
Psoriatic epidermis is associated with upregulation of CDK2 and inhibition of CDK4 activity. Br J Dermatol 2019; 182:678-689. [PMID: 31145809 DOI: 10.1111/bjd.18178] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2019] [Indexed: 01/10/2023]
Abstract
BACKGROUND The cyclin-dependent kinases (CDKs) CDK2 and CDK4 are involved in regulation of cell-cycle progression, and psoriasis is characterized by hyperproliferation of basal epidermal cells. CDK inhibitory proteins (CKIs) such as p16INK 4A (p16) bind CDK4/6 kinases and prevent their interaction with D-type cyclins. CKIs such as p21Cip1 (p21) and p27Kip1 (p27) associate with CDK-cyclin complexes and prevent their activation. OBJECTIVES To gain insight into the molecular implication of CDK2 and CDK4 kinases in psoriasis, we sought to characterize expression of these kinases and associated cyclins, as well as of CKIs, and addressed the status of CDK2 and CDK4 activity in human psoriatic epidermis. METHODS A cohort of 24 patients with psoriasis participated in the study. Biopsies were removed from a chronic plaque and from nonlesional skin. CDK2, CDK4, cyclin D1, cyclin E and CKI protein expression was assessed by immunoblotting, immunohistochemistry and immunofluorescence. CDK4 and CDK2 mRNA expression was determined by real-time polymerase chain reaction. Specific kinase activities of CDK2 and CDK4 were evaluated using fluorescent peptide biosensors. RESULTS CDK2-cyclin E expression and activity were significantly increased in psoriatic epidermis compared with uninvolved adjacent skin. In contrast, CDK4-cyclin D1 activity was inhibited, although its expression was increased in psoriatic epidermis and its transcription slightly inhibited. p27 expression was reduced, while p16 and p21 expression was induced in psoriatic epidermis. CONCLUSIONS Epidermal CDK2 activity is increased in psoriatic epidermis while CDK4 activity is completely inhibited. These alterations are not associated with changes in CDK transcription and instead involve post-translational control mediated by decreased expression of p27 and p16 overexpression, respectively. What's already known about this topic? Cyclin-dependent kinases (CDKs) are involved in cell-cycle progression. The levels of cyclin partners and CDK inhibitors regulate their activity. Psoriasis is a chronic T-cell-driven inflammatory skin disease characterized by hyperproliferation of basal epidermal cells. What does this study add? Thanks to fluorescent peptide biosensors, this study demonstrates that epidermal CDK2 activity is increased in psoriatic epidermis while CDK4 activity is completely inhibited. These alterations involve post-translational control mediated by decreased expression of p27, and p16 overexpression, respectively. What is the translational message? CDK2 and CDK4 are involved in regulation of cell-cycle progression, and psoriasis is characterized by hyperproliferation of basal epidermal cells. Epidermal CDK2 activity is increased in psoriatic epidermis while CDK4 activity is completely inhibited. These alterations are not associated with changes in CDK transcription and instead involve post-translational control mediated by decreased expression of p27 and p16 overexpression, respectively. Pharmacological modulation of CDK2 and CDK4 may constitute a promising therapeutic strategy.
Collapse
|
9
|
Building a Weakly Outgassing Comet from a Generalized Ohm's Law. PHYSICAL REVIEW LETTERS 2019; 123:055101. [PMID: 31491291 DOI: 10.1103/physrevlett.123.055101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 05/21/2019] [Indexed: 06/10/2023]
Abstract
When a weakly outgassing comet is sufficiently close to the Sun, the formation of an ionized coma results in solar wind mass loading and magnetic field draping around its nucleus. Using a 3D fully kinetic approach, we distill the components of a generalized Ohm's law and the effective electron equation of state directly from the self-consistently simulated electron dynamics and identify the driving physics in the various regions of the cometary plasma environment. Using the example of space plasmas, in particular multispecies cometary plasmas, we show how the description for the complex kinetic electron dynamics can be simplified through a simple effective closure, and identify where an isotropic single-electron fluid Ohm's law approximation can be used, and where it fails.
Collapse
|
10
|
|
11
|
Electron and Ion Dynamics of the Solar Wind Interaction with a Weakly Outgassing Comet. PHYSICAL REVIEW LETTERS 2017; 118:205101. [PMID: 28581804 DOI: 10.1103/physrevlett.118.205101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Indexed: 06/07/2023]
Abstract
Using a 3D fully kinetic approach, we disentangle and explain the ion and electron dynamics of the solar wind interaction with a weakly outgassing comet. We show that, to first order, the dynamical interaction is representative of a four-fluid coupled system. We self-consistently simulate and identify the origin of the warm and suprathermal electron distributions observed by ESA's Rosetta mission to comet 67P/Churyumov-Gerasimenko and conclude that a detailed kinetic treatment of the electron dynamics is critical to fully capture the complex physics of mass-loading plasmas.
Collapse
|
12
|
Dialysat au citrate et évolution des PTH en HDF online : étude observationnelle. Nephrol Ther 2016. [DOI: 10.1016/j.nephro.2016.07.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
13
|
Statut social des dialysés « migrants sanitaires » : étude pilote sur quatre centres de dialyse de centres hospitaliers publics. Nephrol Ther 2015. [DOI: 10.1016/j.nephro.2015.07.218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
14
|
Dialysat au citrate et évolution des paramètres minéraux en HDF online : étude observationnelle. Nephrol Ther 2015. [DOI: 10.1016/j.nephro.2015.07.151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
15
|
Abstract
The Rosetta mission shall accompany comet 67P/Churyumov-Gerasimenko from a heliocentric distance of >3.6 astronomical units through perihelion passage at 1.25 astronomical units, spanning low and maximum activity levels. Initially, the solar wind permeates the thin comet atmosphere formed from sublimation, until the size and plasma pressure of the ionized atmosphere define its boundaries: A magnetosphere is born. Using the Rosetta Plasma Consortium ion composition analyzer, we trace the evolution from the first detection of water ions to when the atmosphere begins repelling the solar wind (~3.3 astronomical units), and we report the spatial structure of this early interaction. The near-comet water population comprises accelerated ions (<800 electron volts), produced upstream of Rosetta, and lower energy locally produced ions; we estimate the fluxes of both ion species and energetic neutral atoms.
Collapse
|
16
|
Idle waves in high-performance computing. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:013306. [PMID: 25679738 DOI: 10.1103/physreve.91.013306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Indexed: 06/04/2023]
Abstract
The vast majority of parallel scientific applications distributes computation among processes that are in a busy state when computing and in an idle state when waiting for information from other processes. We identify the propagation of idle waves through processes in scientific applications with a local information exchange between the two processes. Idle waves are nondispersive and have a phase velocity inversely proportional to the average busy time. The physical mechanism enabling the propagation of idle waves is the local synchronization between two processes due to remote data dependency. This study provides a description of the large number of processes in parallel scientific applications as a continuous medium. This work also is a step towards an understanding of how localized idle periods can affect remote processes, leading to the degradation of global performance in parallel scientific applications.
Collapse
|
17
|
Résultats cliniques des 54 premiers patients traités par hémodialyse quotidienne à bas débit de dialysat à domicile en France et en Belgique. Nephrol Ther 2014. [DOI: 10.1016/j.nephro.2014.07.074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
18
|
Incidence et caractéristiques des replis d’auto-dialyse vers les centres lourds dans une région française. Nephrol Ther 2014. [DOI: 10.1016/j.nephro.2014.07.110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
19
|
Natriurèse résiduelle et statut d’hydratation extracellulaire en hémodialyse chronique : une étude observationnelle, multicentrique. Nephrol Ther 2013. [DOI: 10.1016/j.nephro.2013.07.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
20
|
L’hémodiafiltration améliore-t-elle le statut nutritionnel des patients hémodialysés chroniques ? Nephrol Ther 2013. [DOI: 10.1016/j.nephro.2013.07.284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
21
|
Impact de l’utilisation du Continuous Glucose Monitoring System (CGMS) sur l’équilibre glycémique des patients diabétiques en hémodialyse : étude Dialydab. Nephrol Ther 2013. [DOI: 10.1016/j.nephro.2013.07.282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
22
|
Place de l’éculizumab lors de récidives après transplantation rénale d’un syndrome hémolytique et urémique atypique lié à une mutation familiale du gène du C3. Nephrol Ther 2013. [DOI: 10.1016/j.nephro.2013.07.320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
23
|
Is renal allograft dysfunction a risk factor for severe infection in kidney transplant recipients? Transplant Proc 2013; 44:2821-3. [PMID: 23146532 DOI: 10.1016/j.transproceed.2012.09.088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The ANTICIPE study is a cross-sectional, multicenter, French study. The aim of this study was to describe clinical and biological parameters observed in a cohort of 1446 stable renal transplant recipients, according to the stage of chronic kidney disease. Severe infection was defined as an infection necessitating ≥ 7 days of hospital stay. We observed a negative correlation between declining glomerular filtration rate and occurrence of severe infection (P < .0001). In multivariate analysis, severe infection was associated with age, female gender, chronic kidney disease stage (Kidney Disease Outcomes Quality Initiative classification), and number of acute rejection episodes. Our study suggested that renal allograft function is a predictor not only of cardiac death and cardiovascular complications, but also of severe infections.
Collapse
|
24
|
Comparaison de l’épuration du FGF 23 entre l’hémodialyse et l’hémodiafiltration et évolution des taux prédialytiques. Nephrol Ther 2012. [DOI: 10.1016/j.nephro.2012.07.287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
25
|
Transplantés rénaux avec insuffisance rénale chronique : caractéristiques des patients pour lesquels il n’y a pas d’intention de proposer une nouvelle greffe. Nephrol Ther 2012. [DOI: 10.1016/j.nephro.2012.07.092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
26
|
Cardiovascular complications in CKD 5D. Nephrol Dial Transplant 2012. [DOI: 10.1093/ndt/gfs225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
27
|
Évolution de l’état d’hydratation des patients en insuffisance rénale terminale recevant une transplantation rénale. Nephrol Ther 2011. [DOI: 10.1016/j.nephro.2011.07.269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
28
|
Particularités de la maladie rénale chronique des transplantés : comparaison des études Anticipe et Prepare. Nephrol Ther 2011. [DOI: 10.1016/j.nephro.2011.07.291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
29
|
Description de la prise en charge des insuffisants rénaux greffés stades 3b et 4. Étude ANTICIPE. Nephrol Ther 2011. [DOI: 10.1016/j.nephro.2011.07.275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
30
|
Evaluation médico-économique des nouvelles solutions en dialyse péritonéale. Nephrol Ther 2009; 5 Suppl 4:S286-9. [DOI: 10.1016/s1769-7255(09)74560-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
31
|
|
32
|
Is rapid initiation of peritoneal dialysis feasible in unplanned dialysis patients? A single-centre experience. Nephrol Dial Transplant 2008; 23:3290-4. [DOI: 10.1093/ndt/gfn213] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
33
|
|
34
|
[B-flow ultrasonographic imaging of circulating blood]. JOURNAL DE RADIOLOGIE 2000; 81:465-7. [PMID: 10795008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
B-Flow is a new imaging technique which uses General Electric's Digitally Encoded Ultrasound technology to provide direct visualization of blood echoes in grey-scale imaging. This allows simultaneous imaging of blood flow and vessel walls with a high frame rate and high spatial resolution without information on velocity and direction. This promising technique which improves early detection of vascular disease could modify our routine practice in a near future.
Collapse
|
35
|
Grating transition radiation: a source of quasimonochromatic radiation. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 60:6214-7. [PMID: 11970537 DOI: 10.1103/physreve.60.6214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/1999] [Indexed: 04/18/2023]
Abstract
We have observed transition radiation at optical wavelengths, emitted by 3-13-MeV electrons interacting with a diffraction grating. Near the direction of specular reflection we observed broadband radiation with the same properties as optical transition radiation from a flat surface. In addition, at large angles with respect to this direction and for low angles of incidence of the electrons on the grating surface, we observed the emission of quasimonochromatic radiation. This grating transition radiation may offer an alternative method for production of quasimonochromatic radiation in the far-infrared to mm wavelength range.
Collapse
|
36
|
[Trigeminal neuralgia. Diagnosis]. LA REVUE DU PRATICIEN 1998; 48:1387-8. [PMID: 9781202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
|
37
|
[Rheumatoid purpura during pregnancy]. NEPHROLOGIE 1997; 18:27-9. [PMID: 9121602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We report the case of a 26 year old woman who presented a Henoch Schönlein purpura at 13 weeks' gestation. IgA glomerulonephritis without pejoratif feature was confirmed by renal biopsy. Corticosteroid therapy was unsuccessful on nephrotic syndrome. At 25 weeks' gestation foetal death occurred followed by a rapid development of end stage renal failure.
Collapse
|
38
|
[Quantitative detection of pp65 intraleukocyte cytomegalic antigen in renal transplantation]. Presse Med 1995; 24:1731-5. [PMID: 8545412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVE To assess the clinical value of quantitative assay of leukocyte cytomegalovirus antigen (LCA) in the management of immunodepressed patients. METHODS Thirty-three kidney transplant recipients followed a weekly follow-up protocol during the first 3 months after transplantation. LCA was compared with cytomegalovirus (CMV) detection in blood using fibroblast cell culture and with serology tests. LCA was expressed in number of positive cells per 2.10(5) leukocytes, detected by immunofluorescence with a specific monoclonal antibody directed against the pp65 antigen. The standard culture method and a rapid centrifuge method were used for blood samples. The serum level of anti CMV antibodies was determined by ELISA. RESULTS CMV infection defined as positive viraemia and/or positive serology tests was diagnosed in 22 of the 33 patients. LCA was detected in 20 patients, including all those with clinical signs of infection. Serology was the only method giving a positive diagnosis in 2 patients and was negative in 3 infections positive for LCA. Viraemia was negative in 2 patients positive for LCA. LCA was detected in 60 of the 65 blood samples with a positive viraemia test and in 46 of the 165 negative samples (sensitivity 92% and specificity 72%). Quantitatively, LCA in samples taken from patients with clinical signs was higher than that in samples taken from asymptomatic patients (51 +/- 5 versus 20 +/- 2, p < 0.001). In addition, LCA was detected a mean 7.6 +/- 4 days before significant changes in serology tests, 2.2 +/- 1.6 days before the viraemia and 7.1 +/- 1 days before clinical manifestations. CONCLUSION Leukocyte cytomegalovirus antigen gives a sensitive means of early positive diagnosis. The quantified level illustrates the patient's risk of infection. This new method is a very helpful tool in following renal transplantation recipients.
Collapse
|
39
|
Abstract
Two cases reports of interferon alpha-associated nephropathy are reported. The first observation is a membranoproliferative glomerulonephritis and the second a renal microangiopathy. The different cases in the literature are reviewed and the pathophysiology is discussed.
Collapse
|
40
|
[Hypocoagulation caused by thiabendazole-acenocoumarol interaction]. Therapie 1993; 48:500-1. [PMID: 8146845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
41
|
[The resistance of "Pseudomonas" to antibiotics and heavy metal: minimal inhibitory concentrations and genetic transfers (author's transl)]. ANNALES DE MICROBIOLOGIE 1976; 127:57-68. [PMID: 828462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The antibiotic sensitivity of 43 strains of Pseudomonas and the minimal inhibitory concentration of mercurial derivatives (5 mineral salts and 4 organics compounds) and of silver nitrate to these microorganisms have been studied. Twelve of these strains were P. aeruginosa of hospital origin, and 31 were Pseudomonas from surface water. Resistance against these inhibitory substances let us to established some connections between the different strains. Some strains were selected to transfer resistance markers by conjugation.
Collapse
|