Metacyclogenesis of
Trypanosoma cruzi of the Y and Berenice strains was studied in
Triatoma pseudomaculata and
Rhodnius neglectus. Results in vivo showed a higher production of metacyclic ...trypomastigotes in
R. neglectus’ digestive tube than in
T. pseudomaculata. In vitro experiments were also carried out in order to compare the behavior of culture forms of
T. cruzi incubated in extracts of different compartments (stomach, intestine, and rectum) of the digestive tract of both species of triatomines. A higher percentage of metacyclic trypomastigotes for both parasite strains, Y and Berenice, was detected in the rectum extract of
R. neglectus in comparison to that from
T. pseudomaculata. The same results were obtained with in vitro experiments, using parasites incubated in urine from each of those vectors. The adhesion of parasites to the incubated rectum epithelial cells was also compared. In incubations with the Y strain no significant differences were detected between the two triatomine species but, however, with the Berenice strain the mean percentage of cells with adhered parasites was higher in
R. neglectus than in
T. pseudomaculata.
Index Descriptors:
Trypanosoma cruzi; developmental forms; metacyclogenesis;
Rhodnius neglectus;
Triatoma pseudomaculata
Simulation of ion beam cooling with a pulsed electron beam Zhao, H.; Mao, L.J.; Zhang, Y.H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2018, Letnik:
902
Journal Article
Recenzirano
All operational electron cooling systems employ a DC electron beam that generated by an electrostatic electron gun. This paper is devoted to the simulation of the electron cooling process with a ...pulsed electron beam, in which the electron cooling, Intra Beam Scattering and the space-charge field of the pulsed electron beam are included. A simulation of coasting ion beam cooling with a pulsed electron beam showed that the ion beam is cooled down to a small momentum spread, and all ions are captured by the bucket created by the pulsed electron beam space-charge field simultaneously. Finally, a cold pulsed ion beam with length the same as the electron pulse is obtained. In this article, the structure of the particle tracking simulation code is described and the simulation results of coasting and bunched ion beam cooling with a pulsed electron beam are presented and analyzed. Moreover, the preliminary experiment on CSRm is introduced and the result shows an agreement with the simulation.
Few cases of atrial thrombosis detected by transesophageal echocardiography (TEE) in cardiac amyloidosis have been reported recently. We present the cases of 3 consecutive patients affected by ...AL-type cardiac amyloidosis, symptomatic for heart failure and in sinus rhythm. All patients had a cardiac restrictive pattern at Doppler examination. TEE showed left atrial thrombus in 2 patients and biatrial thrombi in 1 patient; conventional transthoracic echocardiography detected only 1 left atrial thrombus. Our experience confirms the association between cardiac amyloidosis and atrial thrombosis, even in sinus rhythm. TEE should be considered to assess thromboembolic risk in all cases of cardiac amyloidosis with severe diastolic dysfunction.
Tilt induced prolonged asystole has been considered to identify a distinct subgroup of patients with neurally mediated syncope and management including permanent pacemaker implantation has been ...suggested. To evaluate the reproducibility of asystolic response during head-up tilt testing (HUT), 33 patients with neurally mediated syncope and asystolic response (> or = 3 seconds) during HUT prospectively underwent two consecutive tests 13 +/- 15 days apart. On repeat tilt testing asystole was reproduced in 12 patients (36%), while 8 patients still had a positive HUT, but without asystole. Remarkably, 13 patients (40%) had a negative repeat HUT. Among 12 patients with asystole on both HUTs there was no significant difference in duration of asystole (14 371 +/- 11 430 ms vs 13 707 +/- 10 470 ms, P = ns) and time to syncope (36 +/- 20 min vs 37 +/- 20 min, P = ns) during initial and repeat HUTs. In conclusion, asystole during tilt testing does not seem to be a reproducible response.
Myocardial involvement is a common finding in patients with Duchenne-type muscular dystrophy (DMD). Nevertheless, the prognostic values of standard electrocardiogram (ECG), ventricular arrhythmias, ...ventricular late potentials (LPs), and left ventricular (LV) systolic dysfunction have not been extensively investigated. Eighty-four patients with DMD (aged 18.6 ± 4.8 years) underwent standard and signal-averaged electrocardiography, 24-hour Holter monitoring, and echocardiography. The prevalence of electrocardiographic abnormalities, frequent ventricular premature complexes, LPs, and LV systolic dysfunction was 71%, 32%, 28%, and 35%, respectively. Median follow-up was 76 months (range 5 to106). The mortality rate in the follow-up period was 27%. The typical DMD electrocardiographic alterations, ventricular arrhythmic pattern, and LPs were not predictors of mortality. In contrast, the presence of LV systolic dysfunction detected on echocardiography was a powerful predictor of mortality in the follow-up period (p = 0.013, hazard ratio 3.14, 95% confidence interval 1.27 to 7.79). Thus, echocardiographic assessment of LV systolic dysfunction provides prognostic information in patients with DMD. Electrocardiographic alterations, ventricular arrhythmias, and LPs have no prognostic value in predicting mortality in these patients.
CEBAF Control Room Renovation Spata, M.; Oren, T.; Cuffe, A. ...
Proceedings of the 2005 Particle Accelerator Conference,
2005
Conference Proceeding
Odprti dostop
The Machine Control Center (MCC) at Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) was initially constructed in the early 1990s and based on proven technology of that era. ...Through our experience over the last 15 years and in our planning for the facility's 12 GeV upgrade we reevaluated the control room environment to capitalize on emerging visualization and display technologies and improve workflow processes and ergonomic attributes. This effort also sets the foundation for the redevelopment of the accelerator's control system to deliver high reliability performance with improvements in beam specifications management and information flow. The complete renovation was performed over a three-week maintenance period with no interruption to beam operations. We present the results of this effort.
Localized basal septal hypertrophy (LSH) is usually an incidental echocardiographic finding and, as opposed to asymmetric hypertrophic cardiomyopathy (AHC), is of no clinical significance. We report ...a case of a patient with LSH who developed a severe left ventricular outflow gradient during acute myocardial ischaemia, apical akinesis and compensatory hyperkinesis of basal parietal segments.
Positron Beams At Ce\(^+\)BAF Grames, J; Benesch, J; Bruker, M ...
arXiv (Cornell University),
09/2023
Paper, Journal Article
Odprti dostop
We present a scheme for the generation of a high polarization positron beam with continous wave (CW) bunch structure for the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson ...Laboratory (JLab). The positrons are created in a high average power conversion target and collected by a CW capture linac and DC solenoid.
Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic ...physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of nucleons and nuclei, in both the elastic and deep-inelastic regimes. For instance, elastic scattering of polarized and unpolarized electrons and positrons from the nucleon enables a model independent determination of its electromagnetic form factors. Also, the deeply-virtual scattering of polarized and unpolarized electrons and positrons allows unambiguous separation of the different contributions to the cross section of the lepto-production of photons and of lepton-pairs, enabling an accurate determination of the nucleons and nuclei generalized parton distributions, and providing an access to the gravitational form factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model of particle physics through the search of a dark photon, the precise measurement of electroweak couplings, and the investigation of charged lepton flavor violation. This document discusses the perspectives of an experimental program with high duty-cycle positron beams at JLab.
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