4,425 research outputs found
Purple People Eater Words
Peter Newby\u27s November 1995 Word Ways article The Anglo-American Hyphen arrived in the same mail until the 2 Dec 1995 issue of Science News. In the Biology column of the latter (page 178), this headline appeared: A TREATMENT PLANT-FISH HATCHERY IN ONE -- reminiscent, perhaps, of a medical facility for plant-fish. But since Providence has provided two symbols to clarify such ambiguities, the following is better: A TREATMENT-PLANT/FISH-HATCHERY IN ONE. With loyal fealty, the article followed the style of its title. It began with a 21 year-word/single-sentence paragraph, almost half of which was a 10-word name: East Chicago Sanitary District Wastewater Treatment Plan near Lake Michigan
Proper Names, Improper Uses
Leonard R. N. Ashley presented a quiz titled The Proper Name in the Proper Use in the February 1995 issue of Word Ways. I worked it. I did my best, and although my answers differ somewhat from Ashley\u27s anyone who has (or has had) a teenage daughter and/or son will surely agree that my answers come as close to the mark (whoever she is) as Ashley\u27s
Surface morphological evolutions on single crystal films by strong anisotropic drift-diffusion under the capillary and electromigration forces
The morphological evolution of voids at the unpassivated surfaces and the
sidewalls of the single crystal metallic films are investigated via computer
simulations by using the novel mathematical model developed by Ogurtani relying
on the fundamental postulates of irreversible thermodynamics. The effects of
the drift-diffusion anisotropy on the development of the surface morphological
scenarios are fully explored under the action of the electromigration (EM) and
capillary forces (CF), utilizing numerous combination of the surface textures
and the directions of the applied electric field. The interconnect failure time
due to the EM induced wedge shape internal voids and the incubation time of the
oscillatory surface waves, under the severe instability regimes, are deduced by
the novel renormalization procedures applied on the outputs of the computer
simulation experiments.Comment: 41 pages, 18 figures. related simulation movies utilizing numerous
combination of the surface texture, see
http://www.csl.mete.metu.edu.tr/aytac/thesis/movies/index.ht
Generating Information-Diverse Microwave Speckle Patterns Inside a Room at a Single Frequency With a Dynamic Metasurface Aperture
We demonstrate that dynamic metasurface apertures (DMAs) are capable of generating a multitude of highly uncorrelated speckle patterns in a typical residential environment at a single frequency. We use a DMA implemented as an electrically-large cavity excited by a single port and loaded with many individually-addressable tunable metamaterial radiators. We placed such a DMA in one corner of a plywood-walled L-shape room transmitting microwave signals at 19 GHz as we changed the tuning states of the metamaterial radiators. In another corner, in the non-line-of-sight of the DMA, we conducted a scan of the field generated by the DMA. For comparison, we also performed a similar test where the DMA was replaced by a simple dipole antenna with fixed pattern but generating a signal that spanned 19-24 GHz. Using singular value decomposition of the scanned data, we demonstrate that the DMA can generate a multitude of highly uncorrelated speckle patterns at a single frequency. In contrast, a dipole antenna with a fixed pattern can only generate such a highly uncorrelated set of patterns when operating over a large bandwidth. The experimental results of this paper suggest that DMAs can be used to capture a diversity of information at a single frequency which can be used for single frequency computational imaging systems, NLOS motion detection, gesture recognition systems, and more
Phase Retrieval with Application to Optical Imaging
This review article provides a contemporary overview of phase retrieval in
optical imaging, linking the relevant optical physics to the information
processing methods and algorithms. Its purpose is to describe the current state
of the art in this area, identify challenges, and suggest vision and areas
where signal processing methods can have a large impact on optical imaging and
on the world of imaging at large, with applications in a variety of fields
ranging from biology and chemistry to physics and engineering
Molecular, genetic, and cellular pathogenesis of neurofibromas and surgical implications
Journal ArticleNEUROFIBROMATOSIS 1 (NF1) IS A common autosomal dominant disease characterized by complex and multicellular neurofibroma tumors. Significant advances have been made in the research of the cellular, genetic, and molecular biology of NF1. The NF1 gene was identified by positional cloning. The functions of its protein product, neurofibromin, in RAS signaling and in other signal transduction pathways are being elucidated, and the important roles of loss of heterozygosity and haploinsufficiency in tumorigenesis are better understood. The Schwann cell was discovered to be the cell of origin for neurofibromas, but understanding of a more complicated interplay of multiple cell types in tumorigenesis, specifically recruited heterogenous cell types such as mast cells and fibroblasts, has important implications for surgical therapy of these tumors. This review summarizes the most recent NF1 and neurofibroma literature describing the pathogenesis and treatment of nerve sheath tumors. Understanding the biological underpinnings of tumorigenesis in NF1 has implications for future surgical and medical management of neurofibromas
Cavernous hemangioma of the skull presenting with subdural hematoma
Journal ArticleCavernous hemangioma of the calvaria is a very rare disease, and patients usually present with headaches or a visible skull deformity. Few reports of patients presenting with intradiploic or epidural hemorrhages are found in the literature. No case of an intradural hemorrhage from a cavernous hemangioma of the skull has been reported to date. The authors present the case of a 50-year-old man in whom a symptomatic subdural hematoma (SDH) resulting from a cavernous hemangioma of the calvaria had hemorrhaged and eroded through the inner table of the skull and dura mater. The patient underwent surgery for evacuation of the SDH and resection of the calvarial lesion. Postoperatively, the patient experienced immediate relief of his symptoms and had no clinical or radiological recurrence. Calvarial cavernous hemangiomas should be considered in the differential diagnosis of nontraumatic SDHs. Additionally, skull lesions that present with intracranial hemorrhages must be identified and resected at the time of hematoma evacuation to prevent recurrences
Neurosurgical workforce trends in the United States
Journal ArticleObject. The purpose of this study was to evaluate the US neurosurgery workforce by reviewing journal recruitment advertisements published during the past 10 years. Methods. The number of available academic and private neurosurgical staff positions was determined based on recruitment advertisements in the Journal of Neurosurgery and Neurosurgery for the 10-year period from 1994 to 2003. Advertisements were evaluated for practice venue, subspecialization, and location. The numbers of active neurosurgeons and graduating residents also were reviewed. The number of advertised neurosurgical positions increased from 141.6 ± 38.2 per year from 1994 through 1998 to 282.4 ± 13.6 per year from 1999 through 2003 (mean 6 standard deviation, p < 0.05). The mean number of academic positions increased from 50.6 ± 11.1 to 95 ± 17.5 (p < 0.05), and the mean number of private positions rose from 91 ± 30.4 to 187.4 ± 6.8 (p < 0.05). Subspecialty positions represented a mean of only 15.6 ± 5% per year during the first time period and 18.8 ± 3% per year in the second period (p = 0.22), and therefore the majority of positions advertised continued to be those for generalists. The number of practicing neurosurgeons declined after 1998, and by 2002 it was less than it had been in 1991. The numbers of incoming and matriculating residents during the study period were static. Conclusions. The number of recruitment advertisements for neurosurgeons during the last 5 years has increased significantly, concomitant with a severe decline in the number of active neurosurgeons and a static supply of residents
Trigeminal amyloidoma: case report and review of the literature
ManuscriptThe authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 trigeminal nerves. The patient underwent extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. There was also enlargement of the gasserian ganglion and second and third divisions of the trigeminal nerve, the latter of which was biopsied. Permanent histopathological studies demonstrated microscopic eosinophilic, amorphous material, which stained positive for Congo red, and absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas may occur from the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. The few reports of trigeminal amyloidomas are reviewed and the presentation, imaging, and management of this skull base lesion are discussed. Overall, patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside of the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction
Adherence to Nutrition and Physical Activity Cancer Prevention Guidelines and Development of Colorectal Adenoma.
Adherence to the American Cancer Society's (ACS) Nutrition and Physical Activity Cancer Prevention Guidelines is associated with reductions in overall cancer incidence and mortality, including site-specific cancers such as colorectal cancer. We examined the relationship between baseline adherence to the ACS guidelines and (1) baseline adenoma characteristics and (2) odds of recurrent colorectal adenomas over 3 years of follow-up. Cross-sectional and prospective analyses with a pooled sample of participants from the Wheat Bran Fiber (n = 503) and Ursodeoxycholic Acid (n = 854) trials were performed. A cumulative adherence score was constructed using baseline self-reported data regarding body size, diet, physical activity and alcohol consumption. Multivariable logistic regression demonstrated significantly reduced odds of having three or more adenomas at baseline for moderately adherent (odds ratio [OR] = 0.67, 95% confidence intervals [CI]: 0.46⁻0.99) and highly adherent (OR = 0.50, 95% CI: 0.31⁻0.81) participants compared to low adherers (p-trend = 0.005). Conversely, guideline adherence was not associated with development of recurrent colorectal adenoma (moderate adherence OR = 1.16, 95% CI: 0.85⁻1.59, high adherence OR = 1.23, 95% CI: 0.85⁻1.79)
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