202 research outputs found

    Inpatient and outpatient loop electrosurgery excision procedure for cervical intraepithelial neoplasia: a retrospective analysis

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    Purpose: To determine whether the outpatient loop electrosurgical excision procedure (LEEP) conization (out-LEEP) is as effective and safe as inpatient LEEP conization (in-LEEP) with regard to the complete removal of cervical dysplasia, recurrence-free survival and post-operative morbidity. Methods: 233 patients were included in this retrospective cohort study from January 2002 to December 2007. 181 had outpatient treatment and 52 inpatient treatment. We used Mann-Whitney U test, two-sided Fisher's exact test, Chi-square test, log rank test and Kaplan-Meier curve. Results: Incomplete excision was found in 16/52 (30.8%) cases in the inpatient group and 46/181 (25.4%) in the outpatient group (P=0.48). Six patients had post-operative complications: two cases of secondary haemorrhage in each group (in-LEEP 3.8%, out-LEEP 1.1%, P=0.22) and two cases of cervical stenosis amongst inpatients (3.8%, P=0.049). Alteration of specimen by thermal artifact were reported in 4/52 (7.7%) of in-LEEP cones and 10/181 (5.5%) of out-LEEP cones (P=0.52). Measurements of cones in both groups were comparable with a mean depth of 9.35mm (Ā±5.5mm) and 8.4mm (Ā±3.4mm), respectively. Conclusion: Our results suggest that efficacy and safety of ambulatory LEEP conization is comparable as in inpatient procedur

    Parallel Iterative Methods

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    In this paper we discuss the implementation of the ITPACK library [Kine 82] in the parallel (//)ELL-PACK environment [Holls 92] and report on its performance on the nCUBE II parallel machine. In this study we are concerned with the numerical solution of second order elliptic partial diITerential equations (PDEs) on rectangular regions with mixed boundary conditions using finite difference approximations. The parallelization methodology applied is based on the domain decomposition of discrete geometric data structures (grids) associated with the numerical solution of the PDE problem[Chri 91]. The implementa-tion of I jITPACK for boundary value problems defined on general 2Ā·0 and 3-D domains for both finite element and difference methods is reported in [Kim 93]. The performance results obtained so far indicate almost optimal computational and space efficiency of the / /ITPACK modules

    Stark shift and parity non-conservation for near-degenerate states of xenon

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    We identify a pair of near-degenerate states of opposite parity in atomic Xe, the 5p^5 10s \,\, ^2[3/2]_2^o at E=94759.927\rm{E}=94759.927 cmāˆ’1^{-1} and 5p^5 6f \,\, ^2[5/2]_2 at E=94759.935\rm{E}= 94759.935 cmāˆ’1^{-1}, for which parity- and time-odd effects are expected to be enhanced by the small energy separation. We present theoretical calculations which indicate narrow widths for both states and we report a calculated value for the weak matrix element, arising from configuration mixing, of āˆ£Wāˆ£=2.1|W|=2.1 Hz for 132^{132}Xe. In addition, we measured the Stark effect of the 5p5ā€‰6f5p^5\,6f 2[5/2]2^2[5/2]_{2} and 5p5ā€‰6fĀ 2[3/2]25p^5 \,6f \ ^2[3/2]_2 (E=94737.121ā€‰cmāˆ’1\rm{E} =94737.121\,\rm{cm}^{-1}) states. The Stark-shift of the 6f6f states is observed to be negative, revealing the presence of nearby 6g6g states at higher energies, which have not been observed before. The Stark-shift measurements imply an upper limit on the weak matrix element of āˆ£Wāˆ£ā€‰ā£<ā€‰ā£5|W|\!<\!5 Hz for the near-degenerate states (10s \,\, ^2[3/2]_2^o and 6f \,\, ^2[5/2]_2), which is in agreement with the presented calculations.Comment: 11 pages, 6 figure

    Ionizing radiation exposure and the development of soft-tissue sarcomas in atomic-bomb survivors

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    BACKGROUND: Very high levels of ionizing radiation exposure have been associated with the development of soft-tissue sarcoma. The effects of lower levels of ionizing radiation on sarcoma development are unknown. This study addressed the role of low to moderately high levels of ionizing radiation exposure in the development of soft-tissue sarcoma. METHODS: Based on the Life Span Study cohort of Japanese atomic-bomb survivors, 80,180 individuals were prospectively assessed for the development of primary soft-tissue sarcoma. Colon dose in gray (Gy), the excess relative risk, and the excess absolute rate per Gy absorbed ionizing radiation dose were assessed. Subject demographic, age-specific, and survival parameters were evaluated. RESULTS: One hundred and four soft-tissue sarcomas were identified (mean colon dose = 0.18 Gy), associated with a 39% five-year survival rate. Mean ages at the time of the bombings and sarcoma diagnosis were 26.8 and 63.6 years, respectively. A linear dose-response model with an excess relative risk of 1.01 per Gy (95% confidence interval [CI]: 0.13 to 2.46; p = 0.019) and an excess absolute risk per Gy of 4.3 per 100,000 persons per year (95% CI: 1.1 to 8.9; p = 0.001) were noted in the development of soft-tissue sarcoma. CONCLUSIONS: This is one of the largest and longest studies (fifty-six years from the time of exposure to the time of follow-up) to assess ionizing radiation effects on the development of soft-tissue sarcoma. This is the first study to suggest that lower levels of ionizing radiation may be associated with the development of soft-tissue sarcoma, with exposure of 1 Gy doubling the risk of soft-tissue sarcoma development (linear dose-response). The five-year survival rate of patients with soft-tissue sarcoma in this population was much lower than that reported elsewhere.published_or_final_versio

    Inverted hysteresis and negative remanence in a homogeneous antiferromagnet

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    Magnetic remanence -- found in bar magnets or magnetic storage devices -- is probably the oldest and most ubiquitous phenomenon underpinning technological applications of magnetism. It is a macroscopic non-equilibrium phenomenon: a remanent magnetisation appears when a magnetic field is applied to an initially unmagnetised ferromagnet, and then taken away. Here, we present an inverted magnetic hysteresis loop in the pyrochlore compound Nd2Hf2O7: the remanent magnetisation points in a direction opposite to the applied field. This phenomenon is exquisitely tunable as a function of the protocol in field and temperature, and it is reproducible as in a quasi-equilibrium setting. We account for this phenomenon in considerable detail in terms of the properties of nonequilibrium population of domain walls which exhibit a magnetic moment between domains of an ordered antiferromagnetic state which itself has zero net magnetisation. Properties and (nonequilibrium) dynamics of topological defects play an important role in modern spintronics, and our study adds an instance where a uniform field couples selectively to domain walls rather than the bulk.Physic

    Magnetic excitation spectrum and Hamiltonian of the quantum spin chain compound BaCuTe2O6

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    AbstractThe magnetic excitation spectrum and Hamiltonian of the quantum magnet BaCuTe2O6 is studied by inelastic neutron scattering (INS) and density functional theory (DFT). INS on powder and single crystal samples reveals overlapping spinon continuaā€”the spectrum of an antiferromagnetic spin-1/2 spin chainā€”due to equivalent chains running along the a, b, and c directions. Long-range magnetic order onsets below TN=6.3 K due to interchain interactions, and is accompanied by the emergence of sharp spin-wave excitations, which replace the continua at low energies. The spin-wave spectrum is highly complex and was successfully modelled achieving excellent agreement with the data. The extracted interactions reveal an intrachain interaction, J3=2.9 meV, while the antiferromagnetic hyperkagome interaction J2 is the subleading interaction responsible for coupling the chains together in a frustrated way. DFT calculations reveal a similar picture for BaCuTe2O6 of dominant J3 and subleading J2 antiferromagnetic interactions and also indicate a high sensitivity of the interactions to small changes of structure, which could explain the very different Hamiltonians observed in the sister compounds SrCuTe2O6 and PbCuTe2O6

    Bone sarcomas in atomic bomb survivors of Hiroshima and Nagasaki

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    Abstract no. 1017PURPOSE/OBJECTIVE(S): Ionizing radiationā€induced bone sarcomas have traditionally been associated with exposure to high levels of ionizing radiation. The role of exposure to lower levels of ionizing radiation in the development of such lesions remains speculative. Also, the appropriate doseā€response model of radiation dose exposure to excess relative risk (ERR) in association with bone sarcomas is questionable. MATERIALS/METHODS: The data source of the longitudinal, populationā€based Life Span Study (N=120,321) cohort of atomic bomb survivors of Hiroshima and Nagasaki was utilized to estimate the ERR per Gray (Gy) of ionizing radiation exposure in the development of bone sarcomas. Other factors regarding sarcoma demographics ā€¦postprin
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