64 research outputs found
Study, design and realization of a Fabry-Perot cavity for the Compton polarimeter of TJNAF; Etude, conception et realisation d'une cavite Fabry-Perot pour le polarimetre Compton de TJNAF
This is a doctoral dissertation, in French, on the subject of study, design and realization of a Fabry-Perot cavity for the Compton polarimeter of TJNAF
Risk factors for Low Anterior Resection Syndrome (LARS) in patients undergoing laparoscopic surgery for rectal cancer
BACKGROUND: Total mesorectal excision (TME) represents the “gold standard” of rectal cancer surgery. In locally advanced lesions neoadjuvant treatments (e.g. radiotherapy-nRT, radio chemotherapy-cnRT) have been shown to improve TME oncological results, reducing local recurrences rate. Nevertheless, these treatments have significant functional consequences impacting patients’ quality of life (QoL). The resulting syndrome is known as Low Anterior Resection Syndrome (LARS). The purpose of this work was to evaluate the association between risk factors and the development of LARS in a prospective series of laparoscopic sphincter-saving TME. METHODS: The study was conducted as a retrospective observational epidemiological study of a prospective database, including all patients undergoing laparoscopic anterior resection surgery for rectal cancer at our Unit from 1st January 2013 to 31st May 2018. The diagnosis of LARS was performed using the LARS Score. We classified risk factors in patient-related, pre-, intra- and post-operative factors. RESULTS: The sample included 153 consecutive patients. Forty-one were affected by “low” rectal cancer, 74 by “middle” rectal cancer, 38 by “high” rectal cancer. The prevalence of overall LARS (major LARS + minor LARS) in our series was 35.9% (55/153 cases). Association between nRT and overall/major LARS was significant (respectively p = 0.03 and 0.02). Distal localization of tumor was also significantly associated with LARS [overall LARS (p = 0.03), major LARS (p = 0.014)]. CONCLUSIONS: In our study, neoadjuvant radiotherapy and tumor localization resulted independent risk factors for LARS after laparoscopic sphincter-saving TME. Tumor localization in the “middle” and “high” rectum resulted a protective factor compared to the localization in “low” rectum
First electron beam polarization measurements with a Compton polarimeter at Jefferson Laboratory
A Compton polarimeter has been installed in Hall A at Jefferson Laboratory.
This letter reports on the first electron beam polarization measurements
performed during the HAPPEX experiment at an electron energy of 3.3 GeV and an
average current of 40 A. The heart of this device is a Fabry-Perot cavity
which increased the luminosity for Compton scattering in the interaction region
so much that a 1.4% statistical accuracy could be obtained within one hour,
with a 3.3% total error
A photon calorimeter using lead tungstate crystals for the CEBAF Hall A Compton polarimeter
The performances of the calorimeter of the Jlab Hall A Compton Polarimeter
have been measured using the Mainz tagged photon beam.Comment: 13 page
Sacral Nerve Stimulation for Treatment of Chronic Intractable Anorectal Pain -A Case Report-
Despite recent methodological advancement of the practical pain medicine, many cases of the chronic anorectal pain have been intractable. A 54-year-old female patient who had a month history of a constant severe anorectal pain was referred to our clinic for further management. No organic or functional pathology was found. In spite of several modalities of management, such as medications and nerve blocks had been applied, the efficacy of such treatments was not long-lasting. Eventually, she underwent temporary then subsequent permanent sacral nerve stimulation. Her sequential numerical rating scale for pain and pain disability index were markedly improved. We report a successful management of the chronic intractable anorectal pain via permanent sacral nerve stimulation. But further controlled studies may be needed
A FABRY-PEROT CAVITY FOR COMPTON POLARIMETRY
A new kind of Compton polarimeter using a resonant Fabry—Pe« rot cavity as a power buildup for the photon beam is proposed. A prototype of such a cavity is described, along with the results obtained in terms of source to be used in a Compton scattering polarimeter. ( 1998 Elsevier Science B.V. All rights reserved
New Measurement of Parity Violation in Elastic Electron-Proton Scattering and Implications for Strange Form Factors
We have measured the parity-violating electroweak asymmetry in the elastic
scattering of polarized electrons from the proton. The result is A = -15.05 +-
0.98(stat) +- 0.56(syst) ppm at the kinematic point theta_lab = 12.3 degrees
and Q^2 = 0.477 (GeV/c)^2. The measurement implies that the value for the
strange form factor (G_E^s + 0.392 G_M^s) = 0.025 +- 0.020 +- 0.014, where the
first error is experimental and the second arises from the uncertainties in
electromagnetic form factors. This measurement is the first fixed-target parity
violation experiment that used either a `strained' GaAs photocathode to produce
highly polarized electrons or a Compton polarimeter to continuously monitor the
electron beam polarization.Comment: 8 pages, 4 figures, Tex, elsart.cls; revised version as accepted for
Phys. Lett.
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A New Type of Compton Polarimeter for Jefferson Lab Hall A
In this paper, we present the principle and the studies for a new type of Compton polarimeter based on the use of power buildup Fabry-Perot cavity to get a 3% measurement of the Jefferson Lab electron polarization within minutes
Rotavirus group : a genotype circulation patterns across Kenya before and after nationwide vaccine introduction, 2010-2018
Background
Kenya introduced the monovalent G1P [8] Rotarix® vaccine into the infant immunization schedule in July 2014. We examined trends in rotavirus group A (RVA) genotype distribution pre- (January 2010–June 2014) and post- (July 2014–December 2018) RVA vaccine introduction.
Methods
Stool samples were collected from children aged < 13 years from four surveillance sites across Kenya: Kilifi County Hospital, Tabitha Clinic Nairobi, Lwak Mission Hospital, and Siaya County Referral Hospital (children aged < 5 years only). Samples were screened for RVA using enzyme linked immunosorbent assay (ELISA) and VP7 and VP4 genes sequenced to infer genotypes.
Results
We genotyped 614 samples in pre-vaccine and 261 in post-vaccine introduction periods. During the pre-vaccine introduction period, the most frequent RVA genotypes were G1P [8] (45.8%), G8P [4] (15.8%), G9P [8] (13.2%), G2P [4] (7.0%) and G3P [6] (3.1%). In the post-vaccine introduction period, the most frequent genotypes were G1P [8] (52.1%), G2P [4] (20.7%) and G3P [8] (16.1%). Predominant genotypes varied by year and site in both pre and post-vaccine periods. Temporal genotype patterns showed an increase in prevalence of vaccine heterotypic genotypes, such as the commonly DS-1-like G2P [4] (7.0 to 20.7%, P < .001) and G3P [8] (1.3 to 16.1%, P < .001) genotypes in the post-vaccine introduction period. Additionally, we observed a decline in prevalence of genotypes G8P [4] (15.8 to 0.4%, P < .001) and G9P [8] (13.2 to 5.4%, P < .001) in the post-vaccine introduction period. Phylogenetic analysis of genotype G1P [8], revealed circulation of strains of lineages G1-I, G1-II and P [8]-1, P [8]-III and P [8]-IV. Considerable genetic diversity was observed between the pre and post-vaccine strains, evidenced by distinct clusters.
Conclusion
Genotype prevalence varied from before to after vaccine introduction. Such observations emphasize the need for long-term surveillance to monitor vaccine impact. These changes may represent natural secular variation or possible immuno-epidemiological changes arising from the introduction of the vaccine. Full genome sequencing could provide insights into post-vaccine evolutionary pressures and antigenic diversity
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