57 research outputs found

    A tribute to Juan Rosai

    Get PDF
    0

    Optoacoustic solitons in Bragg gratings

    Full text link
    Optical gap solitons, which exist due to a balance of nonlinearity and dispersion due to a Bragg grating, can couple to acoustic waves through electrostriction. This gives rise to a new species of ``gap-acoustic'' solitons (GASs), for which we find exact analytic solutions. The GAS consists of an optical pulse similar to the optical gap soliton, dressed by an accompanying phonon pulse. Close to the speed of sound, the phonon component is large. In subsonic (supersonic) solitons, the phonon pulse is a positive (negative) density variation. Coupling to the acoustic field damps the solitons' oscillatory instability, and gives rise to a distinct instability for supersonic solitons, which may make the GAS decelerate and change direction, ultimately making the soliton subsonic.Comment: 5 pages, 3 figure

    Axillary node metastasis from differentiated thyroid carcinoma with hürthle and signet ring cell differentiation. A case of disseminated thyroid cancer with peculiar histologic findings

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Differentiated thyroid cancer is usually associated with an excellent prognosis and indolent course. Distant metastases are rare events at the onset of thyroid cancer. Among these presentations, metastasis to the axillary lymph nodes is even more unusual: only few cases were previously reported in the literature; there has been no report of axillary lymph node metastasis from follicular thyroid carcinoma. Axillary lymph node metastasis generally arises in the context of disseminated disease and carries an ominous prognosis.</p> <p>Case presentation</p> <p>Here we present a case of axillary lymph node metastasis in the context of disseminated differentiated thyroid cancer. The patient underwent near total thyroidectomy and neck and axillary lymph node dissection. A histopathological diagnosis of poorly differentiated follicular carcinoma with "signet ring cells" and Hürthle cell features was established. The patient received radioactive iodine therapy and TSH suppression therapy. Subsequently his serum thyroglobulin level decreased to 44.000 ng/ml from over 100.000 ng/ml.</p> <p>Discussion and Conclusion</p> <p>Currently there are only few reported cases of axillary node metastases from thyroid cancer, and to our knowledge, this is the first report on axillary lymph node metastasis from follicular thyroid carcinoma. "Signet ring cell" is a morphologic feature shared by both benign and, more rarely, malignant follicular thyroid neoplasm, and it generally correlates with an arrest in folliculogenesis. Our case is one of the rare "signet ring cells" carcinomas so far described.</p

    A citizen science approach: A detailed ecological assessment of subtropical reefs at point lookout, Australia

    Get PDF
    Subtropical reefs provide an important habitat for flora and fauna, and proper monitoring is required for conservation. Monitoring these exposed and submerged reefs is challenging and available resources are limited. Citizen science is increasing in momentum, as an applied research tool and in the variety of monitoring approaches adopted. This paper aims to demonstrate an ecological assessment and mapping approach that incorporates both top-down (volunteer marine scientists) and bottom-up (divers/community) engagement aspects of citizen science, applied at a subtropical reef at Point Lookout, Southeast Queensland, Australia. Marine scientists trained fifty citizen scientists in survey techniques that included mapping of habitat features, recording of substrate, fish and invertebrate composition, and quantifying impacts (e.g., occurrence of substrate damage, presence of litter). In 2014 these volunteers conducted four seasonal surveys along semi-permanent transects, at five sites, across three reefs. The project presented is a model on how citizen science can be conducted in a marine environment through collaboration of volunteer researchers, non-researchers and local marine authorities. Significant differences in coral and algal cover were observed among the three sites, while fluctuations in algal cover were also observed seasonally. Differences in fish assemblages were apparent among sites and seasons, with subtropical fish groups observed more commonly in colder seasons. The least physical damage occurred in the most exposed sites (Flat Rock) within the highly protected marine park zones. The broad range of data collected through this top-down/bottomup approach to citizen science exemplifies the projects' value and application for identifying ecosystem trends or patterns. The results of the project support natural resource and marine park management, providing a valuable contribution to existing scientific knowledge and the conservation of local reefs

    Agreement on endoscopic ultrasonography-guided tissue specimens: Comparing a 20-G fine-needle biopsy to a 25-G fine-needle aspiration needle among academic and non-academic pathologists

    Get PDF
    Background and Aim: A recently carried out randomized controlled trial showed the benefit of a novel 20-G fine-needle biopsy (FNB) over a 25-G fine-needle aspiration (FNA) needle. The current study evaluated the reproducibility of these findings among expert academic and non-academic pathologists. Methods: This study was a side-study of the ASPRO (ASpiration versus PROcore) study. Five centers retrieved 74 (59%) consecutive FNB and 51 (41%) FNA samples from the ASPRO study according to randomization; 64 (51%) pancreatic and 61 (49%) lymph node specimens. Samples were re-reviewed by five expert academic and five non-academic pathologists and rated in terms of sample quality and diagnosis. Ratings were compared between needles, expert academic and

    Ovarian mature cystic teratoma with florid vascular proliferation and Wagner-Meissner-like corpuscles

    No full text
    An ovarian mature cystic teratoma featuring florid vascular proliferation and Wagner-Meissner-like corpuscles is presented. The vascular proliferation is analogous to that seen in other tumors having a prominent neural component. The Wagner-Meissner-like corpuscles are viewed as evidence of a specialized type of differentiation of this neural component. To the best of our knowledge, they had not been previously reported in this setting

    Value of autopsy in renal malformations: Comparison of clinical diagnosis and post-mortem examination.

    No full text
    Abstract Background and aim: This 6-year retrospective study reports 14 cases of renal malformations, observed in foetuses and newborns. The objective was to evaluate the usefulness of post-mortem examination in cases of renal malformations by a comparison of the post-mortem findings with clinical diagnosis. Methods: This study included laboratory tests, ultrasonography, karyotype and detailed pathological evaluation of the foetuses and newborns by external, macroscopic, microscopic and placental examination. Results: The resultsof post-mortem examination were of paramount importance: they disclosed renal malformations escaped on prenatal studies (42,86%), provided extensive additional informations (50%), or confirmed the diagnosis hypothesis (7,14%). Conclusions: Thus, this study confirmed the need of pathological examination forfoetuses and newborns, after medical abortion and neonatal death. The pathologist’s contribution to the multidisciplinary management of prenatal or postnatal abnormalities is important in particular for further genetic counseling
    corecore