1,219 research outputs found
The Value of Intraoperative Examination of Axillary Sentinel Nodes in Carcinoma of the Breast.
Abstract Axillary sentinel lymph node biopsy (SLNB) has become the standard of care for T1-2, N-0, M-0 carcinoma of the breast. However, the accuracy of frozen section in the intra-operative examination of sentinel nodes (SN) remains controversial. The senior author has championed the use of the intraoperative examination of SN by frozen section ex-amination from the inception of its use, and we present our experience with frozen section examination of SN, confirming that this technique is both practical and highly accurate. Materials & Methods: Between 2000 and 2007, 236 SLNB procedures were performed that were read as “fro-zen section negative.” SN were identified by 1% lymphazurin blue dye only. The identification of SN in these 236 women was 100%. Each SN specimen was prosected by the senior author; a dedicated surgical pathology technician prepared the frozen sections. Nodes were dissected from the specimen individually and cut at 2.5 to 3.0 mm. intervals. Each of these sections was then cut at three levels. The frozen sections were read by the attending pathologist assigned to frozen sections for that day, not by a dedicated breast pathologist. During the period of the study, 14 different attending pathologists read the slides, with 6 pathologists each reading more than 20 cases. Others read from 1 to14 cases. Results: In this group of 236 cases, 11 patients had positive nodes on subsequent examination of the H&E slides; thus, the false negative rate of intraoperative frozen section was 4.7%, i.e., the frozen section was read as negative but the paraffin sections were posi-tive for metastasis. Therefore, the sensitivity of the negative frozen section was \u3e95%. Nine of the 11 false positives were micrometastases, less than 2 mm diameter, one was considered a macrometastasis, with two areas in one node measuring 2.0 and 2.1 mm each, and one was a sub-micrometastasis. The following variables were compared for significance: Pathologist, nuclear grade, histologic grade, margins, lymphovascular invasion, tumor type (ductal vs lobular), ER & PR values. The only significant variables were lymphovascular invasion (p=.019) and presence of in situ ductal carcinoma (p=.001). Only one of the false negatives was a purely lobular carcinoma (1/11). Discussion: Our data confirm the high accuracy of intraoperative examination of SN, \u3e95%, even without a dedicated breast pathologist reviewing the sections. The missed metastases are likely to be micrometastases, and the likelihood of missing a macrometastasis is \u3c1%. In patients with large primary tumors, presence of in situ ductal carcinoma or if lymphovascular invasion is associated with the tumor, special care should be taken to review these cases more thoroughly since these characteristics of tumors seem to make them more likely than others to have micrometastases to the axillary nodes over-looked
Changing of flight phenology and ecotype expansion of the European corn borer (Ostrinia nubilalis Hbn.) in Hungary Part
The studies aimed to acquire the widest possible information on the annual flight in Hungary of the European corn borer (ECB), Ostrinia nubilalis Hübner (Lepidoptera: Pyralidae). The investigations used biomathematical (Part 1) and graphical (Part 2) evaluation to document changes in the individual population number.The study was conducted in Hungary using ECB moth capture records from the Plant Protection Information System black light trap system (1991–2004). We have drawn conclusions on the appearance of annual flights and the tendency of alterations in flight direction by means of light trap results in four different areas in Hungary. We calculated the flight peak quotients, the individual population numbers of the second flight peak, the distinctions of individual numbers of two flight peaks in this part.As previously published, alterations in flight direction of ECB flights began at different times in Hungary. In the current study, a gradual disappearance of the univoltine ecotype and gradual appearance of the bivoltine ecotype ECB in Hungary is confirmed by the data obtained between 1991–2004. Flight peak quotients and data concerning the second flight peak have confirmed change this process, too: the appearance of a second flight peak in Northwestern Hungary from 1995–1996 (FP = 1.27), the more significant appearance of flights in August in Western Hungary (FP = 1.05) and Northeastern Hungary (FP = 1.45), and a three and four times more individual number of the second flight peak in Southeastern Hungary (FP = 3.44). Flight peak quotients, individual population numbers of the second flight peak, the tendency towards a difference in population number of the two peaks, and size of increase of these values demonstrates the southeastern-northwestern presence of the bivoltine ecotype in Hungary
Brewing of filter coffee
We report progress on mathematical modelling of coffee grounds in a drip filter coffee machine. The report focuses on the evolution of the shape of the bed of coffee grounds during extraction with some work also carried out on the chemistry of extraction. This work was sponsored by Philips who are interested in understanding an observed correlation between the final shape of the coffee grounds and the quality of the coffee. We used experimental data gathered by Philips and ourselves to identify regimes in the coffee brewing process and relevant regions of parameter space. Our work makes it clear that a number of separate processes define the shape of the coffee bed depending on the values of the parameters involved e.g. the size of the grains and the speed of fluid flow during extraction. We began work on constructing mathematical models of the redistribution of the coffee grounds specialised to each region and on a model of extraction. A variety of analytic and numerical tools were used. Furthermore our research has progressed far enough to allow us to begin to exploit connections between this problem and other areas of science, in particular the areas of sedimentology and geomorphology, where the processes we have observed in coffee brewing have been studied
On the order of summability of the Fourier inversion formula
In this article we show that the order of the point value, in the sense of Łojasiewicz, of a tempered distribution and the order of summability of the pointwise Fourier inversion formula are closely related. Assuming that the order of the point values and certain order of growth at infinity are given for a tempered distribution, we estimate the order of summability of the Fourier inversion formula. For Fourier series, and in other cases, it is shown that if the distribution has a distributional point value of order k, then its Fourier series is e.v. Cesàro summable to the distributional point value of order k+1. Conversely, we also show that if the pointwise Fourier inversion formula is e.v. Cesàro summable of order k, then the distribution is the (k+1)-th derivative of a locally integrable function, and the distribution has a distributional point value of order k+2. We also establish connections between orders of summability and local behavior for other Fourier inversion problems
Temporal characteristics of semantic perseverations induced by blocked-cyclic picture naming
When unimpaired participants name pictures quickly, they produce many perseverations
that bear a semantic relation to the target, especially when the pictures are blocked by category.
Evidence suggests that the temporal properties of these "semantic perseverations" may differ from
typical lexical perseverations in aphasia. To explore this, we studied semantic perseverations
generated by participants with aphasia on a naming task with semantic blocking [Schnur, T. T.,
Schwartz, M. F., Brecher, A., & Hodgson, C. (2006). Semantic interference during blocked-cyclic
naming: Evidence from aphasia. Journal of Memory and Language, 54, 199-227]. The properties
of these perseverations were investigated by analyzing how often they occurred at each lag
(distance from prior occurrence) and how time (response-stimulus interval) influenced the lag
function. Chance data sets were created by reshuffling stimulus-response pairs in a manner that
preserved unique features of the blocking design. We found that the semantic blocking
manipulation did not eliminate the expected bias for short-lag perseverations (recency bias).
However, immediate (lag 1) perseverations were not invariably the most frequent, which hints at a source of inconsistency within and across studies. Importantly, there was not a reliable difference
between the lag functions for perseverations generated with a 5 s, compared to 1 s, responsestimulus
interval. The combination of recency bias and insensitivity to elapsed time indicates that
the perseveratory impetus in a named response does not passively decay with time but rather is
diminished by interference from related trials. We offer an incremental learning account of these
findings
Direct photon production with effective field theory
The production of hard photons in hadronic collisions is studied using
Soft-Collinear Effective Theory (SCET). This is the first application of SCET
to a physical, observable cross section involving energetic partons in more
than two directions. A factorization formula is derived which involves a
non-trivial interplay of the angular dependence in the hard and soft functions,
both quark and gluon jet functions, and multiple partonic channels. The
relevant hard, jet and soft functions are computed to one loop and their
anomalous dimensions are determined to three loops. The final resummed
inclusive direct photon distribution is valid to next-to-next-to-leading
logarithmic order (NNLL), one order beyond previous work. The result is
improved by including non-logarithmic terms and photon isolation cuts through
matching, and compared to Tevatron data and to fixed order results at the
Tevatron and the LHC. The resummed cross section has a significantly smaller
theoretical uncertainty than the next-to-leading fixed-order result,
particularly at high transverse momentum.Comment: 42 pages, 9 figures; v2: references added, minor changes; v3: typos;
v4: typos, corrections in (16), (47), (72
International criteria for electrocardiographic interpretation in athletes: Consensus statement.
Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly, advanced by a growing body of scientific data and investigations that both examine proposed criteria sets and establish new evidence to guide refinements. On 26-27 February 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington (USA), to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD
Advancing Long-Term Care Science Through Using Common Data Elements: Candidate Measures for Care Outcomes of Personhood, Well-Being, and Quality of Life
To support the development of internationally comparable common data elements (CDEs) that can be used to measure essential aspects of long-term care (LTC) across low-, middle-, and high-income countries, a group of researchers in medicine, nursing, behavioral, and social sciences from 21 different countries have joined forces and launched the Worldwide Elements to Harmonize Research in LTC Living Environments (WE-THRIVE) initiative. This initiative aims to develop a common data infrastructure for international use across the domains of organizational context, workforce and staffing, person-centered care, and care outcomes, as these are critical to LTC quality, experiences, and outcomes. This article reports measurement recommendations for the care outcomes domain, focusing on previously prioritized care outcomes concepts of well-being, quality of life (QoL), and personhood for residents in LTC. Through literature review and expert ranking, we recommend nine measures of well-being, QoL, and personhood, as a basis for developing CDEs for long-term care outcomes across countries. Data in LTC have often included deficit-oriented measures; while important, reductions do not necessarily mean that residents are concurrently experiencing well-being. Enhancing measurement efforts with the inclusion of these positive LTC outcomes across countries would facilitate international LTC research and align with global shifts toward healthy aging and person-centered LTC models
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