Nevus-Like Appearance of Primary Malignant Melanoma of the Esophagus

The primary malignant melanoma of the esophagus (PMME) is a rare malignant disease, accounting for only 0.1–0.2% of all esophageal neoplasms, and the majority of the patients are diagnosed at advanced stages with poor prognosis. We present here a case of 56-year-old woman with epigastric pain and her endoscopic finding revealed several flat and black pigmented mucosal lesions within the distal portion of the esophagus which looked like flat nevus. The histopathology and immunohistochemical profile of the tissue specimens were diagnostic of malignant melanoma

STATE AND PARAMETER ESTIMATION USING POLARIMETRIC RADAR DATA AND AN ENSEMBLE KALMAN FILTER

The US National Weather Service plans to upgrade the entire operational radar network to polarimetric capability early in the next decade. The goal of this dissertation is to develop methodologies that use polarimetric radar data in mesoscale data assimilation systems with the ensemble Kalman filter (EnKF). To directly assimilate polarimetric radar variables into numerical weather prediction models, two sets of comprehensive polarimetric radar simulators are developed. The observed quantities considered include reflectivities at horizontal and vertical polarizations (ZH and ZV, respectively), the differential reflectivity ZDR, the specific differential phase KDP, and the cross-correlation coefficient ρhv. The simulators are applied to a simulated squll-line system and a supercell storm. Simulated fields exhibit realistic polarimetric signatures that include ZDR and KDP columns, ZDR arc, mid-level ZDR and ρhv rings, and hail signatures along with the bright band signature in the stratiform region and deep reflectivity core in the convective region. These simulators are proven to be useful for validating model microphysics by 1) detecting a problem with the treatment of melting processes and 2) manifesting the limitation of a single-moment microphysics scheme in handling the mechanisms closely linked to the size sorting of precipitation particles.The simpler but more efficient version of the polarimetric simulators is incorporated into the EnKF data assimilation system to define the observation operators. Various experiments are performed to: (1) assess the impact of assimilating additional polarimetric variables in the EnKF system based on a single-moment scheme, (2) simultaneously estimate fundamental microphysical parameters and atmospheric state in the presence of observation operator error due to uncertainty in the microphysical parameters, (3) evaluate the capability of the EnKF system to retrieve model state variables using both conventional and polarimetric radar data when a double-moment microphysics scheme is used.The results based on observing system simulation experiments assuming either a perfect or imperfect prediction model show that the storm analysis is improved when polarimetric variables are assimilated in addition to ZH or in addition to both ZH and radial velocity Vr. The additional polarimetic data are more helpful when state and/or parameter estimation is not very successful using conventional radar data alone. The positive impact of polarimetric data is found in all state variables at all levels and more significant improvement is obtained in microphysical variables when the model error originating from the uncertain microphysical parameters is relatively large. The polarimetric variables are generally more beneficial to the analysis of rain water- and hail-related variables, and of the vertical velocity among the wind comonents.It is also suggested that the polarimetrc variable that contains the most independent information content has the largest positive impact on the analysis. Between ZDR and KDP, ZDR is found to produce a larger positive impact in perfect model experiments because ZDR is less correlated with ZH than KDP is. In the microphysical parameter estimation experiments, KDP is generally more useful where the data are mostly selected from discrete regions of the storm while many of ZDR data seem to overlap ZH in location. The microphysical information provided by additional polarimetric radar data appears to help alleviate the solution non-uniqueness problem. This research is, to our knowledge, the first to directly assimilate (simulated) polarimetric radar data into a numerical weather prediction model

Wave Run-Up Phenomenon on Offshore Platforms: Part 1. Tension Leg Platform

This study reports on an extensive experimental campaign carried out to evaluate non-linear waves applied to offshore structures in extreme marine environments. An offshore tension leg platform (TLP) model was used to observe the waves around a fixed-type offshore structure. The wave amplitude measured in the experiments of this study was indicated as a wave run-up ratio. Both the first-order analysis and the analysis of the entire wave amplitude were described. The experimental results were compared with the calculations from a potential-based code in order to verify the effectiveness of the developed technology

Beyond slurry-cast supercapacitor electrodes: PAN/MWNT heteromat-mediated ultrahigh capacitance electrode sheets

Supercapacitors (SCs) have garnered considerable attention as an appealing power source for forthcoming smart energy era. An ultimate challenge facing the SCs is the acquisition of higher energy density without impairing their other electrochemical properties. Herein, we demonstrate a new class of polyacrylonitrile (PAN)/multi-walled carbon tube (MWNT) heteromat-mediated ultrahigh capacitance electrode sheets as an unusual electrode architecture strategy to address the aforementioned issue. Vanadium pentoxide (V2O5) is chosen as a model electrode material to explore the feasibility of the suggested concept. The heteromat V2O5 electrode sheets are produced through one-pot fabrication based on concurrent electrospraying (for V2O5 precursor/MWNT) and electrospinning (for PAN nanofiber) followed by calcination, leading to compact packing of V2O5 materials in intimate contact with MWNTs and PAN nanofibers. As a consequence, the heteromat V2O5 electrode sheets offer three-dimensionally bicontinuous electron (arising from MWNT networks)/ion (from spatially reticulated interstitial voids to be filled with liquid electrolytes) conduction pathways, thereby facilitating redox reaction kinetics of V2O5 materials. In addition, elimination of heavy metallic foil current collectors, in combination with the dense packing of V2O5 materials, significantly increases (electrode sheet-based) specific capacitances far beyond those accessible with conventional slurry-cast electrodes.ope

The Initial Extent of Malapposition in ST-Elevation Myocardial Infarction Treated with Drug-Eluting Stent: The Usefulness of Optical Coherence Tomography

PURPOSE: The aim of this study is to identify the extent of initial malapposition using optical coherence tomography (OCT) in ST-elevation myocardial infarctions (STEMI) treated with different types of drug-eluting stents (DES). MATERIALS AND METHODS: Twenty four STEMI patients that underwent primary percutaneous coronary intervention (PCI) were enrolled. The OCT and intravascular ultrasound (IVUS) were performed within 72 hours after the primary PCI. Distances between the endo-luminal surface of the strut reflection and the vessel wall and the extent of malapposition were measured and analyzed. RESULTS: Sirolimus-eluting stents (SES), paclitaxel-eluting stents (PES) and zotarolimus-eluting stents (ZES) were deployed in 7 patients (29%), 7 patients (29%) and 10 patients (42%). In total, 4951 struts in 620 mm single-stent segments were analyzed (1463 struts in SES, 1522 in PES, and 1966 in ZES). In strut analysis by OCT, the incidence of malapposition was 17 % (860/4951) and in stent analysis by IVUS, malapposition rate was 21% (5/24). The malapposition rate of strut level using OCT in 5 patients who had malapposition in IVUS was significantly higher than the 19 of those who had not (32 +/- 5% vs. 12 +/- 6%, p = 0.001). In addition, the frequency of malapposition was also significantly different (28% in SES, 11% in PES, 10% in ZES, p = 0.001). The use of SES was an independent predictor of malapposed struts. CONCLUSION: The incidence of malapposition using OCT was quite prevalent in STEMI after primary PCI with DES implantation and SES has especially higher rates of malapposition compared to other DESs.ope

Overexpression and characterization of a thermophilic and hemolytic phospholipase of Vibrio vulnificus cloned in Escherichia coli (phospholipase of V. vulnificus)

A phospholipase (PLase) gene of Vibrio vulnificus was cloned in Escherichia coli and the properties of the gene product were investigated. The PLase structural gene was composed of 1,251 bp, encoding 417 amino acids for a protein with a predicted molecular mass of 47,187 Da including a putative signal sequence. The predicted protein sequence was 87 and 82% identical to those of hemolysins from Vibrio spp. and that of lecithinase from V. cholerae, respectively. A lipid binding motif, GDSL, conserved among various PLases and lipases was also observed. Over-expression of PLase caused inclusion body formation in E. coli, but not that of the PLase subclone without the signal sequence (45 kDa). Purified PLase exhibited hemolytic activity on red blood cells and hydrolyzed phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and soya-lecithin mainly to fatty acid and 1,2-diacylglycerol, indicating that it was a PLase with unique catalytic activity. PLase from V. vulnificus had temperature and pH optimum at 45°C and 7.0 in 50 mM Tris-HCl buffer, respectively, but was quite active at temperatures up to 55°C and in a broad range of pH 5 to 10. The activity of the enzyme was enhanced by divalent cations such as Ca2+, Co2+, Mg2+, and Mn2+, but not by ethylenediaminetetraacetic acid (EDTA).Key words: Phospholipase, Vibrio vulnificus, hemolytic, VplA

Platelet-derived growth factor induces p21/WAF1 promoter in vascular smooth muscle cells via activation of an Sp1 site

AbstractMany studies suggested that cyclin-dependent kinase inhibitor (CDKI) p21 acts as a universal inhibitor of cyclin/CDK catalytic activity. This protein has also been shown to be a component of active cyclin/CDK complexes. In addition, it has recently been suggested that p21 serves as an assembly factor in platelet-derived growth factor (PDGF)-stimulated vascular smooth muscle cells (VSMC). However, little is known concerning the molecular mechanisms by which PDGF induces p21 gene expression in VSMC. In this report we demonstrate that PDGF induces the p21 expression at both the mRNA and protein levels. This increase in p21 gene expression was due to activation of the p21 promoter by PDGF. Through both deletion and mutation analysis of the p21 promoter, we defined a 10-bp sequence that is required for the activation of the p21 promoter by PDGF. In addition, gel shift and supershift assays demonstrated that this PDGF-responsive element binds specifically to the transcription factor Sp1. These results demonstrate that Sp1 mediates PDGF-induced p21 gene expression in VSMC. Moreover, immunoblot and immonoprecipitation analysis showed that the level of hyperphosphorylated retinoblastoma protein (Rb) is increased and the protein is physically associated with Sp1 in PDGF-treated cells, indicating that phosphorylated Rb may play a role in regulating Sp1 to activate p21 expression

Echo Path Transfer Function Estimation for Spectral Subtraction-based Acoustic Echo Suppression

In this study, we propose a novel technique for spectral subtraction (SS)-based acoustic echo suppression (AES). Conventional AES methods based on SS apply fixed weights to the estimated echo path transfer function (EPTF) at the current signal segment and to the EPTF estimated until the previous time interval. We propose a new EPTF estimation approach that adaptively updates the weight parameters in response to abrupt changes in the acoustic environment. From the experiments, we conclude that the developed techniques can be successfully used for the SS-based AES systems