40 research outputs found
A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01
The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics
experiment that will study cosmic rays in the to range and will be installed on the International Space Station
(ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the
space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected
cosmic ray triggers. Part of the \emph{Mir} space station was within the
AMS-01 field of view during the four day \emph{Mir} docking phase of this
flight. We have reconstructed an image of this part of the \emph{Mir} space
station using secondary and emissions from primary cosmic rays
interacting with \emph{Mir}. This is the first time this reconstruction was
performed in AMS-01, and it is important for understanding potential
backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor
stylistic and grammer change
Protons in near earth orbit
The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured
by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at
an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is
parameterized by a power law. Below the geomagnetic cutoff a substantial second
spectrum was observed concentrated at equatorial latitudes with a flux ~ 70
m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated
trajectory and originate from a restricted geographic region.Comment: 19 pages, Latex, 7 .eps figure
Assembly of the Inner Tracker Silicon Microstrip Modules
This note describes the organization of the mechanical assembly of the nearly 4000 silicon microstrip modules that were constructed in Italy for the Inner Tracker of the CMS experiment. The customization and the calibration of the robotic system adopted by the CMS Tracker community, starting from a general pilot project realized at CERN, is described. The step-by-step assembly procedure is illustrated in detail. Finally, the results for the mechanical precision of all assembled modules are reported
Ponte et stratégie de la reproduction chez les femelles du tacaud Trisopterus luscus (Gadidés) du plateau continental de la Galice, nord-ouest de l'Espagne
[EN] Pouting, Trisopterus luscus is harvested commercially on the Galician shelf by the Spanish inshore artisanal fleet. In spite of a substantial decrease in pouting catches, fishery regulations are limited to size length restrictions. This study provides biological data including length-at-maturity based on histological methods, seasonal maturation, spawning and fecundity. A collection 443 females, from 17 to 42 cm in total length, were sampled from landings (December 2003 to December 2004). Pouting length-at-maturity was estimated as 19.2 cm on average. Pouting females in spawning condition were observed throughout the year and the number of developing oocytes ranged from 20 000 to 1 327 000. Peak spawning was observed between February and April, which correlated well with trends in gonadosomatic index, and inverse to condition factor and hepatosomatic index. Histological examination of the gonads revealed that pouting ovarian development organization is asynchronous, and fecundity is probably determinate.[FR] Le tacaud, Trisopterus luscus est pêché par la flotte artisanale espagnole. En dépit d'une diminution substantielle des captures de tacaud, la pêche est réglementée uniquement à partir d'une taille minimum commerciale. Cette étude fournit des données biologiques comprenant la taille à maturité sexuelle basée sur l'histologie, la maturation saisonnière, la ponte et la fécondité. Un échantillon de 443 femelles, de 17 à 42 cm longueur totale, est examiné à partir des débarquements durant une année (de décembre 2003 à décembre 2004). La taille moyenne à maturité sexuelle est estimée à 19,2 cm. Les femelles de tacaud en condition de ponte sont observée tout au long de l'année et le nombre d'ovocytes s'étend de 20 000 to 1 327 000 par individu. Les pics de ponte sont observés entre février et avril, ce qui est bien corrélé avec l'évolution du rapport gonado-somatique et inverse de celle du facteur de condition et du rapport hépato-somatique. L'étude histologique révèle que le développement ovarien chez le tacaud est asynchrone, et que la fécondité est probablement déterminée.Peer reviewe
An atypical case of pulmonary embolism from a jugular vein
Neck venous malformations and their potentially life-threatening complications are rarely reported in the available literature. Cases of aneurysmal or hypo-plastic jugular vein thrombosis associated with systemic embolization have not been frequently reported. We present the case of a 60-year-old male, without any known risk factors for thromboembolic disease, admitted for sudden onset dyspnea. The physical examination was remarkable for a right lateral cervical mass, expanding with Valsalva maneuver. Thoracic CT with contrast established the diagnosis of bilateral pulmonary embolism and raised the suspicion of superior vena cava and right atrial thrombosis. Bedside transthoracic echocardiography confirmed the presence of a large right atrial thrombus, with intermittent protrusion through the tricuspid valve. Systemic thrombolysis with Alteplase was initiated shortly after diagnosis, in parallel with unfractionated heparin, with complete resolution of the intracavitary thrombus documented by echocardiography. The patient showed significant improvement in symptoms and was later started on oral anticoagulation. Computed vascular tomography of the neck was performed before discharge, showing hypoplasia of the left internal jugular vein and aneurismal dilation of the contralateral internal jugular vein, without thrombosis. There were no identifiable systemic causes for thrombosis. Surgical resection of the aneurismal jugular vein was excluded, because of its potential to cause intracranial hypertension. The preferred therapeutic option in this case was long-term oral anticoagulation
Right ventricular dysfunction by 3D echocardiography is the best predictor for death and re-hospitalization in patients with heart failure with reduced ejection fraction
Abstract
Background
In patients with heart failure with reduced ejection fraction (HFrEF), right ventricular (RV) size and dysfunction by 2-dimensional echocardiography (2DE) were identified as risk factors for mortality and morbidity, but 3-dimensional echocardiography (3DE) enabled itself as a more reproducible and accurate method.
Aim
To assess the comparative prognostic value of parameters of RV size and dysfunction, measured by 2DE and 3DE, in patients with ischemic and non-ischemic HFrEF, on optimal clinical care, at long-term follow-up.
Methods
142 consecutive patients (62±12 yrs, 104 males) with HFrEF, in sinus rhythm, were assessed by 2DE and 3DE, including RV full-volume acquisitions. RV diameter (RVd), RV end-systolic (RV_EDA) and end-diastolic areas (RV_ESA), RV fractional area change (RVFAC), and 2D_TAPSE were measured by 2DE. RV end-diastolic (RV_EDV) and end-systolic volumes (RV_ESV), RV ejection fraction (RV_EF), and 3D_TAPSE were measured by a dedicated 3DE software. Patients were followed for 37±16 months after the index event. Primary outcome was cardiac death (CD). Secondary outcomes were: 1) HF hospitalizations (HFH); 2) a composite cardiac events (CE) end-point of CD or HFH, myocardial infarction, coronary revascularization, arrhythmias, or CRT.
Results
38 CD, 47 HFH, and 62 CE occurred during follow-up. Mean RVd was 34±7 mm, RV_EDA 20±11 cm2, RV_ESA 12±5 cm2, RV_FAC 37±13%, RV_EDV 84±25 ml/m2, RV_ESV 52±22 ml/m2, and RV_EF 39±10%. Mean 2D_TAPSE was 18±4 mm, while mean 3D_TAPSE was 16±4 mm. By 2DE, only RV_ESA and RV_FAC, but not RV_EDA or RVd, correlated with CD, HFH, and CE. 2D_TAPSE correlated with HFH, but not with CD or CE, while 3D_TAPSE correlated with all primary and secondary outcomes. By 3DE, RV_ESV, but not RV_EDV, correlated with CD, HFH, and CE. Moreover, 3D RV_EF had better correlations with primary and secondary outcomes than 2D RV_FAC (z=3.8, z=2.5, and z=2.5, all p<0.01). By multivariate linear regression analysis including RV_ESA, RV_FAC, RV_ESV, RV_EF, and 3D_TAPSE, only RV_EF was an independent predictor for CD and HFH (r2=0.68 and r2=0.30, both p<0.001).
Conclusion
In patients with ischemic and non-ischemic HFrEF, 3DE parameters of RV size and dysfunction are better predictors for death and re-hospitalization than 2DE parameters. The RV_EF measured by 3DE was the best predictor for death in patients with HFrEF.
Funding Acknowledgement
Type of funding source: None
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P4361New speckle tracking multi-layer approach of myocardial deformation provides additional insights into the heart failure patterns
An atypical case of pulmonary embolism from a jugular vein
Neck venous malformations and their potentially life-threatening complications are rarely reported in the available literature. Cases of aneurysmal or hypo-plastic jugular vein thrombosis associated with systemic embolization have not been frequently reported. We present the case of a 60-year-old male, without any known risk factors for thromboembolic disease, admitted for sudden onset dyspnea. The physical examination was remarkable for a right lateral cervical mass, expanding with Valsalva maneuver. Thoracic CT with contrast established the diagnosis of bilateral pulmonary embolism and raised the suspicion of superior vena cava and right atrial thrombosis. Bedside transthoracic echocardiography confirmed the presence of a large right atrial thrombus, with intermittent protrusion through the tricuspid valve. Systemic thrombolysis with Alteplase was initiated shortly after diagnosis, in parallel with unfractionated heparin, with complete resolution of the intracavitary thrombus documented by echocardiography. The patient showed significant improvement in symptoms and was later started on oral anticoagulation. Computed vascular tomography of the neck was performed before discharge, showing hypoplasia of the left internal jugular vein and aneurismal dilation of the contralateral internal jugular vein, without thrombosis. There were no identifiable systemic causes for thrombosis. Surgical resection of the aneurismal jugular vein was excluded, because of its potential to cause intracranial hypertension. The preferred therapeutic option in this case was long-term oral anticoagulation. Learning points: Internal jugular venous malformations, such as aneurisms or hypoplasia, could be associated with an increased risk of thrombosis and major embolic events. Systemic thrombolysis can be an efficient solution in cases of pulmonary embolism with right heart thrombosis. Multimodality imaging is greatly valuable in clarifying the diagnosis of atypical cases
Left atrial function assessed by 3-dimensional echocardiography is an independent predictor for mortality in heart failure with reduced ejection fraction
Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant TE 137/2020
Background. Patients with heart failure and reduced ejection fraction (HFrEF) are at high risk for death. So far, left ventricular ejection fraction (LVEF) measured by 2-dimensional echocardiography (2DE) has been considered the main predictor of mortality in HFrEF. However, there are new echo parameters reflecting cardiac remodeling, assessed by 3-dimensional echocardiography (3DE), that might improve risk stratification in HFrEF.
Aim. To assess comparative prognostic value of left heart function and remodeling parameters, measured by 2DE versus 3DE, in patients with HFrEF.
Methods. 142 consecutive patients (60 ± 17 years, 91 males), diagnosed with HFrEF, in sinus rhythm, were assessed by 2DE, using dedicated views for the LV and left atrium (LA), and by 3DE, with full-volume multi-beat acquisitions of the LV and LA. Left ventricular volumes (LVVs) were measured from 2DE views, using the modified Simpson biplane method, and from 3DE using dedicated software. Maximal and minimal indexed LAVs were measured from 2DE, using the biplane area-length formula (2D_LAVmax and 2D_LAVmin); and from 3DE, using dedicated software package (3D_LAVmax and 3D_LAVmin). Patients were followed for 5 years (57 ± 11 months) after the index event. Primary outcome was mortality. Secondary outcomes were a composite endpoint (CE) of death and hospitalization for heart failure (HHF); HHF; and a composite cardiac events end-point (MACE) of death, HHF, myocardial infarction, coronary revascularization, arrhythmias, or cardiac resynchronization therapy.
Results. At 5 years we recorded 52 deaths, 70 CE, 36 HHF, and 73 MACE. At baseline, mean 2DE and 3DE LVEFs were 32 ± 10% and 32 ± 9%, respectively.
There was no significant difference between the LVVs or LVEF by 2DE or 3DE between survivors and non-survivors. However, there was a significant difference for total and indexed 2D_LAVmax, 3D_LAVmax, and 3D_LAVmin (Table 1) between survivors and non-survivors.
Similarly, there was no significant correlations with endpoints for the 2DE or 3DE LVVs. However, total and indexed 2D_LAVmax correlated with death, CE, HFH, and MACE, all with P &lt; 0.03. Furthermore, total and indexed 3D_LAVmax, and 3D_LAVmin correlated with death, CE, HFH, and MACE, all with P &lt; 0.05.
In a linear multivariate regression model, that included 2DE and 3DE LVEF, indexed 2D and 3D LAV max and min, only indexed 3D_LAVmin was an independent predictor for death (p &lt; 0.001), CE (p = 0.005), HFH (p = 0.009) and MACE (p = 0.006).
Furthermore, by ROC analysis, an indexed LAV of 30 ml/m2 by 3DE was able to predict death ( Sb 94%, Sp 80%, AUC 0.70), CE (Sb 98%, Sp 80%, AUC 0.67), HFH (Sb 96%, Sp 80%, 0.67), and MACE (Sb 93%, Sp 76%, AUC 0.66).
Conclusion. LVEF by 2DE and 3DE, while smaller in non-survivors, was unable to predict death in a small cohort of patients with HFrEF. However, LAVs, particularly by 3DE, were able to predict cardiac events, suggesting the potential key value of evolving cardiac substrate. Abstract Table 1
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