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Complete response of skull base inverted papilloma to chemotherapy: Case report.
BackgroundInverted papilloma (IP) is the most common benign sinonasal neoplasm. Endoscopic techniques, improved understanding of pathophysiology, and novel surgical approaches have allowed rhinologists to treat IPs more effectively, with surgery being the mainstay of therapy. Frontal sinus IP poses a challenge for surgical therapy due to complex anatomy and potentially difficult surgical access.ObjectivesWe reported a unique case of a massive frontal sinus IP that presented with intracranial and orbital extension, with near resolution after chemotherapy.MethodsA retrospective case review of a patient with a frontal sinus IP treated at a tertiary academic medical center.ResultsA 75-year-old male patient presented with nasal obstruction, purulent nasal discharge, and a growing left supraorbital mass. Endoscopy demonstrated a mass that filled both frontal and ethmoid sinuses, with orbital invasion. There also was substantial erosion of the posterior table, which measured 1.73 × 1.40 cm. A biopsy specimen demonstrated IP with carcinoma in situ. The patient was deemed unresectable on initial evaluation and, subsequently, underwent chemotherapy (carboplatin and paclitaxel). The tumor had a dramatic response to chemotherapy, and the patient elected for definitive surgery to remove any residual disease. During surgery, only a small focus of IP was found along the superior wall of the frontal sinus. No tumor was found elsewhere, including at the site of skull base erosion. The final pathology was IP without carcinoma in situ or dysplasia.ConclusionThis was the first reported case of chemotherapeutic "debulking" of IP, which facilitated surgical resection, despite substantial intracranial and orbital involvement. Although nearly all IPs can be treated surgically, rare cases, such as unresectable tumors, may benefit from systemic chemotherapy
Fracture toughness and crack-resistance curve behavior in metallic glass-matrix composites
Nonlinear-elastic fracture mechanics methods are used to assess the fracture toughness of bulk metallic glass (BMG) composites; results are compared with similar measurements for other monolithic and composite BMG alloys. Mechanistically, plastic shielding gives rise to characteristic resistance-curve behavior where the fracture resistance increases with crack extension. Specifically, confinement of damage by second-phase dendrites is shown to result in enhancement of the toughness by nearly an order of magnitude relative to unreinforced glass
Exploring the Oxygen Order in Hg-1223 and Hg-1201 by 199Hg MAS NMR
We demonstrate the use of a high-resolution solid-state fast (45 kHz) magic
angle spinning (MAS) NMR for mapping the oxygen distribution in Hg-based
cuprate superconductors. We identify observed three peaks in 199Hg spectrum as
belonging to the different chemical environments in the HgO? layer with no
oxygen neighbors, single oxygen neighbor, and two oxygen neighbors. We discuss
observed differences between Hg-1201 and Hg-1223 materials.Comment: 4 pages, 2 figures included. Submitted to NATO Advanced Research
Workshop Proceedings (Miami January 2004
A Population-Based Surveillance Study of Shared Genotypes of Escherichia coli Isolates from Retail Meat and Suspected Cases of Urinary Tract Infections.
There is increasing evidence that retail food may serve as a source of Escherichia coli that causes community-acquired urinary tract infections, but the impact of this source in a community is not known. We conducted a prospective, population-based study in one community to examine the frequency of recovery of uropathogenic E. coli genotypes from retail meat samples. We analyzed E. coli isolates from consecutively collected urine samples of patients suspected to have urinary tract infections (UTIs) at a university-affiliated health service and retail meat samples from the same geographic region. We genotyped all E. coli isolates by multilocus sequence typing (MLST) and tested them for antimicrobial susceptibility. From 2016 to 2017, we cultured 233 E. coli isolates from 230 (21%) of 1,087 urine samples and 177 E. coli isolates from 120 (28%) of 427 retail meat samples. Urine samples contained 61 sequence types (STs), and meat samples had 95 STs; 12 STs (ST10, ST38, ST69, ST80, ST88, ST101, ST117, ST131, ST569, ST906, ST1844, and ST2562) were common to both. Thirty-five (81%) of 43 meat isolates among the 12 STs were from poultry. Among 94 isolates in the 12 STs, 26 (60%) of 43 retail meat isolates and 15 (29%) of 51 human isolates were pan-susceptible (P < 0.005). We found that 21% of E. coli isolates from suspected cases of UTIs belonged to STs found in poultry. Poultry may serve as a possible reservoir of uropathogenic E. coli (UPEC). Additional studies are needed to demonstrate transmission pathways of these UPEC genotypes and their food sources.IMPORTANCE Community-acquired urinary tract infection caused by Escherichia coli is one of the most common infectious diseases in the United States, affecting approximately seven million women and costing approximately 11.6 billion dollars annually. In addition, antibiotic resistance among E. coli bacteria causing urinary tract infection continues to increase, which greatly complicates treatment. Identifying sources of uropathogenic E. coli and implementing prevention measures are essential. However, the reservoirs of uropathogenic E. coli have not been well defined. This study demonstrated that poultry sold in retail stores may serve as one possible source of uropathogenic E. coli This finding adds to a growing body of evidence that suggests that urinary tract infection may be a food-borne disease. More research in this area can lead to the development of preventive strategies to control this common and costly infectious disease
Phreatomagmatic deposits and stratigraphic reconstruction at Debunscha Maar (Mt Cameroon volcano)
The Debunscha Maar (DM) is located on the southwest flank of Mount Cameroon, an active stratovolcano on the Cameroon volcanic line (CVL). Here, we present the physical characteristics of the pyroclastic deposits at DM with the aim of deciphering tephra emplacement mechanisms, evolution of water–magma interaction and reconstructing the stratigraphy beneath the maar. From GPS measurements, the crater has long and short axes of 500 m and 320 m, respectively. Generally, the pyroclastic deposits are well stratified and present a variety of depositional bed forms including structureless/massive beds, massive beds with faint internal stratifications, inversely graded beds, lens- shaped units, impact sags, cross lamination, planar beds as well as dune-like beds. Clast sizes include ash, lapilli-tuff, bombs and blocks (pyroclastic breccia), with
clast lithologies consisting of entrained lithics of porous ankaramite pillow lavas, lithified sediments (sandstone and shale) and juvenile material. The porous ankaramite pillow lavas have glassy margins and vesicle zonations typical of pillow lavas formed by subaqueous eruption. The pillow fragments are more common in early-formed eruption products at the base of the deposit. The lithified sandstones show planar laminations and together with the shales occur predominantly in stratigraphic positions above the
ankaramite pillow lavas. The juvenile materials include basaltic bombs with low vesicularity (b15%) and moderate vesicularity (15–50%). The bombs have chilled surfaces and their abundance increases towards the top of the deposit. The presence of accretionary lapilli, fragments of country-rock and juvenile clasts with ragged surfaces as well as curved and chilled margins, is unambiguous evidence in support of phreatomagmatic activity. Of the observed lithic clasts, only the pillow lavas would appear to have the porosity necessary to furnish the required amount of water to feed the phreatomagmatic maar eruption. The
clast stratigraphy suggests that the maar is underlain by ankaramite pillow lava that erupted on a consolidated sedimentary substratum. Studying deposits resulting from maar eruptions has a direct implication for hazards assessment at areas of active maar volcanism because many surface processes occur around such volcanoes well after the eruptive activities have stopped
Pressurizing Field-Effect Transistors of Few-Layer MoS2 in a Diamond Anvil Cell
Hydrostatic pressure applied using diamond anvil cells (DAC) has been widely
explored to modulate physical properties of materials by tuning their lattice
degree of freedom. Independently, electrical field is able to tune the
electronic degree of freedom of functional materials via, for example, the
field-effect transistor (FET) configuration. Combining these two orthogonal
approaches would allow discovery of new physical properties and phases going
beyond the known phase space. Such experiments are, however, technically
challenging and have not been demonstrated. Herein, we report a feasible
strategy to prepare and measure FETs in a DAC by lithographically patterning
the nanodevices onto the diamond culet. Multiple-terminal FETs were fabricated
in the DAC using few-layer MoS2 and BN as the channel semiconductor and
dielectric layer, respectively. It is found that the mobility, conductance,
carrier concentration, and contact conductance of MoS2 can all be significantly
enhanced with pressure. We expect that the approach could enable unprecedented
ways to explore new phases and properties of materials under coupled
mechano-electrostatic modulation.Comment: 15 pages, 5 figure
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