1,720,963 research outputs found
On the approaching geodesics property
No full textWe survey some recent results and open questions on the approaching geodesics property and its application to the study of the Gromov and horofunction compactifications of a proper geodesic Gromov metric space. We obtain results on the dynamics of isometries and we exhibit an example of a Gromov hyperbolic domain of C which does not satisfy the approaching geodesic property
The horofunction boundary of a Gromov hyperbolic space
No full textWe highlight a condition, the approaching geodesics property, on a proper
geodesic Gromov hyperbolic metric space, which implies that the horofunction
compactification is topologically equivalent to the Gromov compactification. It
is known that this equivalence does not hold in general. We prove using
rescaling techniques that the approaching geodesics property is satisfied by
bounded strongly pseudoconvex domains of endowed with the
Kobayashi metric. We also show that bounded convex domains of
with boundary of finite type in the sense of D'Angelo satisfy a weaker
property, which still implies the equivalence of the two said
compactifications. As a consequence we prove that on those domains big and
small horospheres as defined by Abate coincide. Finally we generalize the
classical Julia's lemma, giving applications to the dynamics of non-expanding
maps
The Neoadjuvant Net: a patient- and surgeon-friendly device to facilitate safe breast-conserving surgery in patients who underwent neoadjuvant treatment
No full textThe primary goal of the study was to describe an innovative and helpful tool in defining the minimal surgical margins necessary during breast-conserving surgery (BCS) after neoadjuvant treatment: the Neoadjuvant Net (NN). The secondary endpoint was to assess its usefulness in achieving postoperative disease-free margins and reducing Ipsilateral Breast Tumor Recurrences (IBRTs). The breast-conserving surgical technique together with the use of the Neoadjuvant Net is herein reported. Age, stage at diagnosis, clinical and pathological response, lymph node status, type of surgery, margin status, and incidence of local and distant recurrence were retrospectively analyzed. Seventy-five patients underwent BCS following medical treatment from 2000 to 2011. The majority of the patients had significant size reduction (63/75, 84%). Twenty-two had a complete clinical response but only 11 (11/75, 14.7%) showed a complete pathological response. Two patients (2/75, 2.67%) had infiltrated surgical margins. After a mean follow-up of seventy months, 3 patients (3/75, 4%) had IBRTs and 4 women had distant metastases (4/75, 5.34%). The NN is an easy-to-use, non-invasive instrument designed with the purpose of facilitating the surgeon's task of reducing infiltrated margins and IBTRs
Reply to letter: "effectiveness of sentinel lymph node intraoperative examination in 753 women with breast cancer: are we overtreating patients?"
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Nipple discharge: is its significance as a risk factor for breast cancer fully understood? Observational study including 915 consecutive patients who underwent selective duct excision.
No full textNipple discharge (ND) is a common symptom seen in breast cancer clinics. The primary aim of this study was to identify preoperative risk factors for breast cancer in patients with pathologic ND. The secondary aim was to assess the clinical and pathological effectiveness of physical examination, galactography, cytological examination of the discharge, selective duct excision and ductoscopy. All patients operated on between 1975 and 2008 who presented with ND as their only symptom was analyzed. Discharge's characteristics, cytological data and galactography reports were recorded. The relationship between each individual finding and the risk of breast cancer was calculated. For each diagnostic tool, the sensitivity, specificity and complication rates were calculated and compared. Nine-hundred-fifteen patients underwent selective duct excision. Two-hundred-nineteen patients (23.9%) were found to be affected by carcinoma. In 100/330 (30.3%) patients with bloody discharge and in 42/239 (17.6%) patients with serous secretion cancer was detected (P = 0.004, P = 0.013, respectively). Patients with sero-sanguinous or coloured discharge had the same risk of cancer as the population analyzed (23.9%, P = NS). Galactographic finding of irregular stenosis seemed to be associated with a higher risk of cancer (P = 0.0001). Cytological findings C5 and C4 were associated with cancer (P = 0.001). Selective duct excision showed highest sensitivity and specificity. In conclusion, the well established role of bloody secretion is confirmed. The supposed benign aetiology of serous, coloured or sero-sanguinous discharge is questionable. The high specificity of the cytological exam justifies routine examination of the ND. Selective duct excision can be considered as the diagnostic gold-standard
EFFECTIVENESS OF SENTINEL LYMPH NODE INTRAOPERATIVE EXAMINATION IN 753 WOMEN WITH BREAST CANCER: ARE WE OVERTREATING PATIENTS?
No full textOBJECTIVE:
The goal of our study was to evaluate the sensitivity and specificity of sentinel lymph node biopsy (SLNB) frozen section (FS) examinations to detect metastatic lymph nodes and also its potential role in avoiding unnecessary demolitive axillary surgery.
BACKGROUND:
SLNB is the standard of care in surgical oncology of the breast. Intraoperative evaluation of the SLN seems to achieve sufficient sensitivity for macrometastasis (Ma), leading to axillary lymph node dissection (ALND) only when strictly necessary. Is it equally as clear when to perform ALND if micrometastasis (Mi) or isolated tumor cells (ITCs) are detected?
METHODS:
All consecutive patients from January 2005 to September 2010 operated on for breast cancer were prospectively enrolled. All patients underwent an FS SLNB. The sensitivity and specificity of SLN FSs in detecting Ma, Mi, and ITCs was calculated. All patients with Ma or Mi at FS underwent ALND. For all patients who underwent ALND, the number of metastatic non-SLNs was recorded and correlated to the size of the SLN metastasis.
RESULTS:
A total of 753 patients were enrolled. FS examination had an overall 54% sensitivity and 100% specificity in detecting metastatic disease (Ma/Mi/ITCs). The sensitivity rises to 89% if only Mas were considered and to 64% if Mas and Mis were counted together. All patients with Mas or Mis detected at FS had a completion ALND during the same procedure (156/222). All patients with Mas detected at final pathology (16 false negatives, 2.6%) and 50 women with Mis or ITCs (119 false negatives, 20%) underwent a delayed ALND. When Mis or ITCs were detected in the SLN, only 8 of 73 (10.9%) and none of 4 (0%) patients, respectively, had at least 1 metastatic non-SLN after ALND. Two patients (2/460, 0.43%) who had negative SLNs showed local axillary recurrence. After a mean follow-up of 32 months, none of the 71 patients with Mis or ITCs who did not undergo a second operation showed local recurrence.
CONCLUSIONS:
SLNB FS is highly effective in detecting the subgroup of patients who may benefit from completion ALND during the same surgical procedure. The role of Mi/ITCs in the SLN(s) is still unclear, but our data lean toward a less aggressive surgical approach
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