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Cutaneous endometriosis.
Cutaneous endometriosis is a disorder that primarily affects women of reproductive age. The disorder is most commonly associated with cyclical pain during menses, but it can be difficult to diagnose in the absence of these symptoms and requires biopsy testing for a definitive diagnosis. We report on a case of a 41-year-old patient undergoing hormonal therapy for infertility who presented with a painful firm subcutaneous nodule in the umbilicus. She was ultimately diagnosed with cutaneous endometriosis and underwent surgical excision. In this report, we discuss the differential diagnosis and comment on treatment options, including surgical excision with wide margins or treatment with hormonal agents, such as danazol or leuprolide. Finally, we discuss whether patients with cutaneous endometriosis should receive an additional evaluation for pelvic endometriosis
Distribution System Outage Detection using Consumer Load and Line Flow Measurements
An outage detection framework for power distribution networks is proposed.
Given the tree structure of the distribution system, a method is developed
combining the use of real-time power flow measurements on edges of the tree
with load forecasts at the nodes of the tree. A maximum a posteriori detector
{\color{black} (MAP)} is formulated for arbitrary number and location of
outages on trees which is shown to have an efficient detector. A framework
relying on the maximum missed detection probability is used for optimal sensor
placement and is solved for tree networks. Finally, a set of case studies is
considered using feeder data from the Pacific Northwest National Laboratories.
We show that a 10\% loss in mean detection reliability network wide reduces the
required sensor density by 60 \% for a typical feeder if efficient use of
measurements is performed.Comment: Complete rework of result
Tracking the Equator Into the Paleogene (abstract of paper presented at AGU Fall Meeting, San Francisco, 8-12 Dec 2003)
Stratigraphy has been compiled for 63 tropical Pacific drill sites that sample lower Neogene and Paleogene sediments. These Sites derive from drilling on DSDP Leg 5 through ODP Leg 199. All Sites have been put on the biostratigraphic and paleomagnetic timescale refined by Leg 199 scientists. Sediment accumulation rates have been calculated for ten intervals ranging in age from 10 Ma to 56 Ma. A simple fixed hotspot model was used for Pacific lithospheric plate rotation in reconstructing the position of the selected sites for each of these ten intervals. The reconstruction of all intervals show the development of a tongue of relatively high accumulation rates associated with the oceanographic divergence at the geographic equator. The estimated position of the geographic equator based on these reconstructions lies consistently south of the position of the equator based on the rotation model used. However, the southward displacement is generally 2 degrees of latitude or less. We believe that this relatively small disagreement between the two estimates of equatorial position back to 56 Ma indicates: 1) Whatever hotspot movement that may have occurred in the interval between 40 and 56 Ma did not affect the motion of the Pacific plate; its motion after 40 Ma appears to have been approximately the same as before 40 Ma. 2) The estimated rate of true polar wander during the interval of 40 - 56 Ma must be very small (~0.125/m.y.) and is probably not significant (i.e., well within the error of these reconstructions)
Investigations of polygonal patterned ground in continuous Antarctic permafrost by means of ground penetrating radar and electrical resistivity tomography: Some unexpected correlations
The results of a combined geophysical and geomorphological investigation of thermal-contraction-crack polygons near Gondwana station (Germany) in northern Victoria Land (Antarctica) are reported. An area of about 20,000 m2 characterized by random orthogonal polygons was investigated using integrated ground penetrating radar, electrical resistivity tomography, geomorphological surveys, and two trench excavations. The polygons are well developed only at elevations higher than 6â7 m above current sea level on Holocene-age raised beaches. It is concluded that the polygons are composite in nature because the shallow linear depressions that outline the polygons are underlain by fissures that can contain both sandy gravel and foliated ice (i.e., ice wedges) even in the same polygon network and at distances of just a few meters. Unexpectedly, most of the polygons follow the border of the raised beaches and develop in correspondence with stratigraphic layers dipping toward the sea, imaged by ground penetrating radar (GPR) profiles and interpreted as prograding layers toward the present-day shoreline
Contact of Single Asperities with Varying Adhesion: Comparing Continuum Mechanics to Atomistic Simulations
Atomistic simulations are used to test the equations of continuum contact
mechanics in nanometer scale contacts. Nominally spherical tips, made by
bending crystals or cutting crystalline or amorphous solids, are pressed into a
flat, elastic substrate. The normal displacement, contact radius, stress
distribution, friction and lateral stiffness are examined as a function of load
and adhesion. The atomic scale roughness present on any tip made of discrete
atoms is shown to have profound effects on the results. Contact areas, local
stresses, and the work of adhesion change by factors of two to four, and the
friction and lateral stiffness vary by orders of magnitude. The microscopic
factors responsible for these changes are discussed. The results are also used
to test methods for analyzing experimental data with continuum theory to
determine information, such as contact area, that can not be measured directly
in nanometer scale contacts. Even when the data appear to be fit by continuum
theory, extracted quantities can differ substantially from their true values
Stratigraphy of Cretaceous to Lower Pliocene sediments in the northern part of Cyprus based on comparative 87Sr/86Sr isotopic, nannofossil and planktonic foraminiferal dating
New age data from Sr isotope analysis and both planktonic foraminifera and nannofossils are presented and discussed here for the Upper EoceneâUpper Miocene sedimentary rocks of the DeÄirmenlik (Kythrea) Group. New dating is also given of some Cretaceous and Pliocene sediments. In a revised stratigraphy the DeÄirmenlik (Kythrea) Group is divided into ten formations. Different Upper Miocene formations are developed to the north and south of a regionally important, EâW-trending syn-sedimentary fault. The samples were dated wherever possible by three independent methods, namely utilizing Sr isotopes, calcareous nannofossils and planktonic foraminifera. Some of the Sr isotopic dates are incompatible with the nannofossil and/or the planktonic foraminiferal dates. This is mainly due to reworking within gravity-deposited or current-affected sediments. When combined, the reliable age data allow an overall biostratigraphy and chronology to be erected. Several of the boundaries of previously defined formations are revised. Sr data that are incompatible with well-constrained biostratigraphical ages are commonly of Early Miocene age. This is attributed to a regional uplift event located to the east of Cyprus, specifically the collision of the Anatolian (Eurasian) and Arabian (African) plates during Early Miocene time. This study, therefore, demonstrates that analytically sound Sr isotopic ages can yield geologically misleading ages, particularly where extensive sediment reworking has occurred. Convincing ages are obtained when isotopic dating is combined with as many forms of biostratigraphical dating as possible, and this may also reveal previously unsuspected geological events (e.g. tectonic uplift or current activity)
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