215 research outputs found
Treatment of patients with distant metastases from phyllodes tumor of the breast
BACKGROUND: Here, the treatment methods and results of patients with phyllodes tumor of the breast (PT) with distant metastases at a single institution are presented. METHODS: A retrospective analysis was performed on a group of 295 patients with PT treated from 1952 to 2010. RESULTS: Distant metastases developed in 37 (12.5Â %) patients; 3/160 (1.9Â %) patients had benign PT, 6/36 (16.7Â %) were considered borderline, and 28/99 (28.3Â %) had malignant PT. Most frequently, the metastases were located in the lungs; 28 (75.7Â %), bone 7 (18.9Â %), brain 4 (10.8Â %), and liver 2 (5.4Â %). Metastases occurred on overage 21Â months (2â57) after surgery. Patients with lung metastases were generally treated with monochemotherapy or polychemotherapy. In one patient Testosterone and in two patients resection of metastases combined with Doxorubicin were used. Patients with bones or brain metastases were treated with palliative radiotherapy only or combined with Doxorubicin. The mean survival (MS) from diagnosis of distant metastases (DM) was 7Â months (2â17). The longest mean survival in patients with bones metastases was 11.8Â months, the worst survival was for patients with brain metastasesâ2.8Â months. Hormone therapy appeared to have low efficacy (MS: 2Â months) as well as monochemotherapy (MS: 3â5Â months). Improved MS was obtained using Doxorubicin (7Â months) and Doxorubicin with Cisplatin, Cyclophosphamide, or Ifosfamide (9Â months). CONCLUSION: The prognosis of patients with DM from PT is poor. The role of surgery and irradiation of such patients is very limited. There appears to be no role for the use of hormone therapy. This study showed that polychemotherapy with Doxorubicin and Ifosfamide suggest that it might be more effective than once thought
The role of accelerated hyperfractionated radiotherapy in the treatment of inoperable non-small celi lung cancer: a controlled clinical trial
Desingularization of vortices for the Euler equation
We study the existence of stationary classical solutions of the
incompressible Euler equation in the plane that approximate singular
stationnary solutions of this equation. The construction is performed by
studying the asymptotics of equation -\eps^2 \Delta
u^\eps=(u^\eps-q-\frac{\kappa}{2\pi} \log \frac{1}{\eps})_+^p with Dirichlet
boundary conditions and a given function. We also study the
desingularization of pairs of vortices by minimal energy nodal solutions and
the desingularization of rotating vortices.Comment: 40 page
Regularization of point vortices for the Euler equation in dimension two
In this paper, we construct stationary classical solutions of the
incompressible Euler equation approximating singular stationary solutions of
this equation.
This procedure is carried out by constructing solutions to the following
elliptic problem [ -\ep^2 \Delta
u=(u-q-\frac{\kappa}{2\pi}\ln\frac{1}{\ep})_+^p, \quad & x\in\Omega, u=0, \quad
& x\in\partial\Omega, ] where , is a bounded
domain, is a harmonic function.
We showed that if is simply-connected smooth domain, then for any
given non-degenerate critical point of Kirchhoff-Routh function
with the same strength , there is a
stationary classical solution approximating stationary points vortex
solution of incompressible Euler equations with vorticity .
Existence and asymptotic behavior of single point non-vanishing vortex
solutions were studied by D. Smets and J. Van Schaftingen (2010).Comment: 32page
Nucleon density of 172Yb and 176Yb at the nuclear periphery determined with antiprotonic x rays
Simulations of galactic dynamos
We review our current understanding of galactic dynamo theory, paying
particular attention to numerical simulations both of the mean-field equations
and the original three-dimensional equations relevant to describing the
magnetic field evolution for a turbulent flow. We emphasize the theoretical
difficulties in explaining non-axisymmetric magnetic fields in galaxies and
discuss the observational basis for such results in terms of rotation measure
analysis. Next, we discuss nonlinear theory, the role of magnetic helicity
conservation and magnetic helicity fluxes. This leads to the possibility that
galactic magnetic fields may be bi-helical, with opposite signs of helicity and
large and small length scales. We discuss their observational signatures and
close by discussing the possibilities of explaining the origin of primordial
magnetic fields.Comment: 28 pages, 15 figure, to appear in Lecture Notes in Physics "Magnetic
fields in diffuse media", Eds. E. de Gouveia Dal Pino and A. Lazaria
bound states in nuclei
The energies and widths of bound states of the meson in different
nuclei are obtained using the results for its selfenergy in a nuclear medium,
which is evaluated in a selfconsistent manner using techniques of unitarized
chiral perturbation theory. We find bound states in all studied nuclei (from
on) and the half widths obtained are larger than the separation of
the levels, what makes the experimental observation of peaks unlikely. We have
paid a special attention to the region of nuclei where only the state
appears and the binding energies are of the order of magnitude of the half
width, which would magnify the chances that some broad peak could be observed.
This is found in the region of with a binding energy around 12.6
MeV and half width of 16.7 MeV. In heavy nuclei like there are
many bound states which would be difficult to disentangle and the deepest state
has a binding energy about 21 MeV and half width around 16 MeV. Such an
overlapping accumulation of states could be seen as an extension of the
continuum of strength into the bound region in production
experiments.Comment: 9 pages, Latex, 2 Figure
Towards transnational feminist queer methodologies
This article introduces the possibilities of transnational feminist queer research as seeking to conceptualise the transnational as a methodology composed of a series of flows that can augment feminist and queer research. Transnational feminist queer methodologies can contest long-standing configurations of power between researcher and researched, subject and object, academics and activists across places, typically those which are embedded in the hierarchies of the Global North/Global South. Beginning with charting our roots in, and routes through, the diverse arenas of transnational, feminist, participatory and queer methodologies, the article uses a transcribed and edited conversation between members of the Liveable Lives research team in Kolkata and Brighton, to start an exploration of transnational feminist queer methodologies. Understanding the difficult, yet constructive moments of collaborative work and dialogue, we argue for engagements with the multiplicities of âmany-many' lives that recognise local specificities, and the complexities of lives within transnational research, avoiding creating a currency of comparison between places. We seek to work toward methodologies that take seriously the politics of place, namely by creating research that answers the same question in different places, using methods that are created in context and may not be âcomparable'. Using a dialogue across the boundaries of activism/academia, as well as across geographical locations, the article contends that there are potentials, as well as challenges, in thinking ourselves through transnational research praxis. This seeks complexities and spatial nuances within as well as between places
Endonuclease-independent LINE-1 retrotransposition at mammalian telomeres
Long interspersed element-1 (LINE-1 or L1) elements are abundant, non-long-terminal-repeat (non-LTR) retrotransposons that comprise 17% of human DNA(1). The average human genome contains similar to 80-100 retrotransposition- competent L1s (ref. 2), and they mobilize by a process that uses both the L1 endonuclease and reverse transcriptase, termed target-site primed reverse transcription(3-5). We have previously reported an efficient, endonuclease-independent L1 retrotransposition pathway (ENi) in certain Chinese hamster ovary (CHO) cell lines that are defective in the non-homologous end-joining (NHEJ) pathway of DNA double-strand-break repair(6). Here we have characterized ENi retrotransposition events generated in V3 CHO cells, which are deficient in DNA-dependent protein kinase catalytic subunit (DNA-PKcs) activity and have both dysfunctional telomeres and an NHEJ defect. Notably, similar to 30% of ENi retrotransposition events insert in an orientation-specific manner adjacent to a perfect telomere repeat (5'-TTAGGG-3'). Similar insertions were not detected among ENi retrotransposition events generated in controls or in XR-1 CHO cells deficient for XRCC4, an NHEJ factor that is required for DNA ligation but has no known function in telomere maintenance. Furthermore, transient expression of a dominant-negative allele of human TRF2 ( also called TERF2) in XRCC4-deficient XR-1 cells, which disrupts telomere capping, enables telomere-associated ENi retrotransposition events. These data indicate that L1s containing a disabled endonuclease can use dysfunctional telomeres as an integration substrate. The findings highlight similarities between the mechanism of ENi retrotransposition and the action of telomerase, because both processes can use a 3' OH for priming reverse transcription at either internal DNA lesions or chromosome ends(7,8). Thus, we propose that ENi retrotransposition is an ancestral mechanism of RNA-mediated DNA repair associated with non-LTR retrotransposons that may have been used before the acquisition of an endonuclease domain.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62964/1/nature05560.pd
Theory and Applications of Non-Relativistic and Relativistic Turbulent Reconnection
Realistic astrophysical environments are turbulent due to the extremely high
Reynolds numbers. Therefore, the theories of reconnection intended for
describing astrophysical reconnection should not ignore the effects of
turbulence on magnetic reconnection. Turbulence is known to change the nature
of many physical processes dramatically and in this review we claim that
magnetic reconnection is not an exception. We stress that not only
astrophysical turbulence is ubiquitous, but also magnetic reconnection itself
induces turbulence. Thus turbulence must be accounted for in any realistic
astrophysical reconnection setup. We argue that due to the similarities of MHD
turbulence in relativistic and non-relativistic cases the theory of magnetic
reconnection developed for the non-relativistic case can be extended to the
relativistic case and we provide numerical simulations that support this
conjecture. We also provide quantitative comparisons of the theoretical
predictions and results of numerical experiments, including the situations when
turbulent reconnection is self-driven, i.e. the turbulence in the system is
generated by the reconnection process itself. We show how turbulent
reconnection entails the violation of magnetic flux freezing, the conclusion
that has really far reaching consequences for many realistically turbulent
astrophysical environments. In addition, we consider observational testing of
turbulent reconnection as well as numerous implications of the theory. The
former includes the Sun and solar wind reconnection, while the latter include
the process of reconnection diffusion induced by turbulent reconnection, the
acceleration of energetic particles, bursts of turbulent reconnection related
to black hole sources as well as gamma ray bursts. Finally, we explain why
turbulent reconnection cannot be explained by turbulent resistivity or derived
through the mean field approach.Comment: 66 pages, 24 figures, a chapter of the book "Magnetic Reconnection -
Concepts and Applications", editors W. Gonzalez, E. N. Parke
- âŠ