cssi/SciSciGPT-SciSciNet huggingface dataset:
Active centers in the polymerization of ethylene using titanium tetrachloride–alkylaluminum catalysts

A method was developed to measure the active centers in a titanium tetrachloridealkylaluminum catalyst system for the polymerization of ethylene. The method depends on the assertion that the active carbon atom of the growing chain is relatively basic and will react with alcohol-O-t. The tritium becomes incorporated in the polymer. The relationship used is N = AG/a, where N is the corrected active center concentration, A is the radioactivity of the polyethylene in counts/min./g., G is the polymer concentration at the time of sampling and a is the specific activity of the quench methanol-O-t in counts/min./mole. The data were corrected for the kH/kT isotope effect of 3.7 which was measured for the alcohol-O-t reaction. This isotope effect was unchanged over a wide range of molecular weights and reaction conditions. The basicity of the carbon on the growing polymer chain was proved by quenching the reaction with C14-labelled alcohol. The resulting polymer was not radioactive. The values of N could be correlated with polymerization rates. Values of the active center concentration and polymer chain lifetime were calculated as a function of molecular weight using fractionated polymer. The centers are very heterogeneous and the lifetimes of polymer chains range from 1 to 30 min. (with an average of 4 min. for the particular conditions used). Calculated values of viscosity- (Mv) and number-average molecular weights as a function of time of reaction agreed well with the experimental data. Because of the long lifetime of some chains, a steady state in Mv is not reached, and Mv increases throughout the course of the reaction. Catalyst efficiency was calculated from a knowledge of N. The efficiency, which can vary from 0.3 to 15% based on the titanium, is a function of how the catalyst components are brought together. The value of N in these systems is about 10−3 to 10−4 moles/liter compared to 10−7 to 10−9 for the concentration of active species in free radical systems. The value of the propagation constant, kp, is comparable in both systems. It is concluded that the very rapid polymerization rate in these heterogeneous systems is due solely to high values of N. These high values of N argue against bimolecular termination of centers. The stability of the centers when refluxed under argon support this idea and cast doubt on chain termination via hydride ion transfer or transfer to solvent. The value for the activation energy of kp is 11.8 over the range of 40 to 68°C. The value of the activation energy for initiation of centers is deduced to be 11.8 kcal./mole, also.
Effects of Soybean Row Spacing on Spray Penetration and Efficacy of Insecticides Applied with Aerial and Ground Equipment

Kromecote® or water-sensitive cards were placed at three or four vertical levels within the canopy of wide (96.5–101.1 cm) and narrow (17.8–25.4 cm) rows of soybeans, Glycine max (L.) Merrill, to measure spray penetration and droplet characteristics of insecticides applied with aerial or ground equipment. Larval mortality data were used to measure the efficacy of the insecticides at three vertical strata within the two row-spacing systems. The size of the droplets deposited was generally smaller within all levels of the narrow-row canopy compared to the wide-row canopy. The total number of drops per cm2 and mean percentage of coverage was reduced in the narrow-row spacing compared to the wide-row spacing, but only within the median one-third of the canopy. Similarly, the percentage of larval mortality was reduced within the median one-third of the narrow-row plots compared to the wide-row plots at the same level. The variable combination of drops per cm2 and number median diameter was significantly correlated ( R = 0.6535) with the percentage of reductions of lepidopterous larval populations of the soybean looper, Pseudoplusia includens (Walker), velvetbean caterpillar, Anticarsia gemmatalis Hubner, and green cloverworm, Plathypena scabra (Fab.).
DESIGN AND EXPERIMENTAL CHARACTERIZATION OF A PM1 AND A PM2.5 PERSONAL SAMPLER

This paper presents the development, laboratory and field evaluation of two personal particle samplers (PPS). Both samplers operate at a flow rate of 4 l min-1, and collect particles smaller than 1.0 and 2.5 μm in aerodynamic diameter, respectively, on 3.7 cm Teflon filters. In each sampler, particles larger than 2.5 or 1.0 μm are retained by impaction onto a coated porous metal disk, which minimizes particle bounce. Using the substrates without any coating results in a substantial reduction of the collection efficiency for particles larger than the 50% cutpoint of the sampler. Particle losses in each sampler are quite low (e.g., on the order of 10% or less) and do not depend significantly on aerodynamic particle diameter. Both samplers display sharp particle cut characteristics, with the ratio of the aerodynamic particle diameter corresponding to 84% collection efficiency to the 50% cutpoint being approximately 1.18 and 1.27 for the PM1 and the PM2.5 samplers, respectively. Field tests showed that the mass, sulfate and nitrate concentrations measured by the PM2.5 PPS and a collocated PM2.5 Personal Exposure Monitor (PEM) agreed within 10% or less. Such agreement, however, was not observed between the PM2.5 PPS and the Harvard/EPA Annular Denuder System (HEADS), with the HEADS nitrate concentrations being on the average higher by a factor of 2.1. The particle mass, sulfate and nitrate concentrations obtained with a modified MOUDI sampler collecting all particles smaller than 1 μm in aerodynamic diameter on a filter and the PM1 PPS were also in very good agreement (e.g., within 7% or less). The two personal particle samplers will be used in field studies in different locations of the U.S. to provide better estimates of human exposures to exclusively particles of the accumulation mode. (e.g., without incorporating the contribution of the coarse mode).
DATA DIFFERENTIATION AND CARTOGRAPHIC SYMBOLIZATION

The study examines three types of data differentiation and the relationships between them and cartographic symbolization. The differentiation of point, line, area, and volume data generally corresponds to the use of point, line, and area symbols. There are exceptions to the general rule, of which the use of point symbols for area data in aggregate form is most common in mapping. Data may or may not be processed prior to symbolization. Processed data often require different methods of symbolization from raw data. Data can be differentiated according to nominal, ordinal, interval, or ratio scale. It has been suggested in the literature that symbolization should depend upon the level of measurement. This study explores problems related to this guideline, namely, the combination of measurement scales in a thematic map, the correspondence between measurement scale and map symbol, and the effect of data classification. L'etude examine trois types de differenciation de donnees, et les rapports qui existent entre...
Evolution of dendritic nanosheets into durable holey sheets: a lattice gas simulation study

Monte Carlo lattice gas simulations are performed to study sintering in a realistic dendritic platinum nanosheet. The morphological and topological transformations observed in the simulations are in good agreement with sintering experiments. Employing an intuitive method of quantifying surface area, the stability of the surface area of the dendritic nanosheets is analyzed. The surface area is found to have a double exponential decay, one decay corresponding to rapid coarsening of dendritic features into pores and the other decay corresponding to a slow disappearance of unstable pores. Long duration simulations indicate that the thickness of the dendritic nanosheet remains fairly stable. Stability simulations of a single model pore in a sheet establish that there exists a narrow range of sheet thickness and pore size combinations that produces stable holey sheets. Outside this parameter range pores either rapidly close or expand without bound. The thickness of the engineered dendritic platinum nanosheet and the size of the crevices between dendritic arms put the Pt sheet into this stable range, further corroborating the detailed simulations and explaining the persistence of pores observed in actual dendritic platinum nanosheets.
Midterm Results of the Modified Ross/Konno Procedure in Neonates and Infants

Background The management of congenital aortic stenosis in neonates and infants continues to be a surgical challenge. We have performed the modified Ross-Konno procedure for patients who have severe aortic insufficiency or significant residual stenosis after balloon aortic dilation. The midterm results of this procedure were evaluated in this subset of patients. Methods Between 1994 and 2010, a total of 24 patients younger than 1 year of age underwent the modified Ross-Konno procedure. The diagnoses were aortic stenosis with or without subaortic stenosis (n = 16), Shone's complex (n = 7), and interrupted aortic arch with subaortic stenosis (n = 1). The aortic root was replaced with a pulmonary autograft, and the left ventricular outflow tract (LVOT) was enlarged with a right ventricular infundibular free wall muscular extension harvested with the autograft. Results Age at operation ranged from 1 to 236 days (median 28 days). The median follow-up period was 81 months (range 1–173 months). There was 1 early death and no late mortality. Overall the 1-, 2-, and 5-year survival rate was 95% ± 4.5%. Freedom from aortic stenosis was 94.7% ± 5.1% at 1, 2, and 5 years. Less than mild aortic insufficiency was 93.3% ± 6.4% at 2 years, and 74.7% ± 12.9% at 5 years. In total, 23 reoperations and reinterventions were performed; 14 were allograft conduit replacements. Two patients required aortic valve plasty. None required valve replacement. The reintervention-free rate was 64.6% ± 10.8% at 2 years and 36.9% ± 11.3% at 5 years. Conclusions Pulmonary autografts demonstrated good durability with low mortality and morbidity. This study shows that the modified Ross-Konno procedure can be a practical choice in selective cases for complex LVOT stenosis in neonates and infants.
Enhanced activity of gold-supported cobalt oxide for the electrochemical evolution of oxygen.

Scanning electron microscopy, linear sweep voltammetry, chronoamperometry, and in situ surface-enhanced Raman spectroscopy were used to investigate the electrochemical oxygen evolution reaction (OER) occurring on cobalt oxide films deposited on Au and other metal substrates. All experiments were carried out in 0.1 M KOH. A remarkable finding is that the turnover frequency for the OER exhibited by ∼0.4 ML of cobalt oxide deposited on Au is 40 times higher than that of bulk cobalt oxide. The activity of small amounts of cobalt oxide deposited on Pt, Pd, Cu, and Co decreased monotonically in the order Au > Pt > Pd > Cu > Co, paralleling the decreasing electronegativity of the substrate metal. Another notable finding is that the OER turnover frequency for ∼0.4 ML of cobalt oxide deposited on Au is nearly three times higher than that for bulk Ir. Raman spectroscopy revealed that the as-deposited cobalt oxide is present as Co3O4 but undergoes progressive oxidation to CoO(OH) with increasing anodic potential. Th...
MTAP: the motif tool assessment platform.

Background In recent years, substantial effort has been applied to de novo regulatory motif discovery. At this time, more than 150 software tools exist to detect regulatory binding sites given a set of genomic sequences. As the number of software packages increases, it becomes more important to identify the tools with the best performance characteristics for specific problem domains. Identifying the correct tool is difficult because of the great variability in motif detection software. Consequently, many labs spend considerable effort testing methods to find one that works well in their problem of interest.
CVD-Co/Cu(Mn) integration and reliability for 10 nm node

In studying integrated dual damascene hardware at 10 nm node dimensions, we identified the mechanism for Co liner enhancement of Cu gap-fill to be a wetting improvement of the PVD Cu seed, rather than a local nucleation enhancement for Cu plating. We then show that Co “divot” (top-comer slit void defect) formation can be suppressed by a new wet chemistry, in turn eliminating divot-induced EM degradation. Further, we confirm a relative decrease in Cu-alloy seed proportional resistivity impact compared to scattering at scaled dimensions, and finally we address the incompatibility between the commonly-used carbonyl-based CVD-Co process with Cu-alloy seed EM performance This problem is due to oxidation of Ta(N) barriers at the TaN/CVD-Co interface by carbonyl-based CVD processes, which then consumes alloy atoms before they can segregate at the Cu/cap interface. We show that O-free CVD-Co may solve this problem. The above solutions may then enable CVD-Co/Cu-alloy seed integration in advanced nodes.
Estimation of electromagnetic parameters and thickness of a wall using synthetic aperture radar

One of the challenges of using synthetic aperture radar (SAR) to detect and classify an object behind a wall consists of determining the amount of signal attenuation introduced by the signal's propagation through the wall. This attenuation is difficult to determine because the electromagnetic properties of the wall, along with its thickness are normally not known a priori . We describe a procedure for determining the necessary parameters given that the SAR has high enough resolution such that the front and the rear surfaces of a uniform wall or cinder block wall can be determined from the SAR image. In addition, we provide a procedure for estimating the signal level behind the wall, or equivalently the attenuation due to the wall, from measured returns from its front and rear surfaces. We demonstrate the effectiveness of this procedure using data generated by XPATCH simulations.
Successful minority pedagogy in mathematics: US and Japanese case studies

This study examines best practices in teaching mathematics to minority students through two case studies conducted at high-minority junior high schools in the USA and Japan. Observations, interviews, and conversations with the teachers in both countries focused on the research question: how do teachers successfully teach mathematics to minority students? Moses’ Five-step Approach was used as a framework for understanding mathematics teaching. Findings from these case studies reveal that despite many differences in their educational systems, distinct similarities existed between US and Japanese pedagogy when teaching minority populations including: (1) building upon students’ prior experiences by using multisensory methods before teaching abstract concepts and rules; (2) using familiar, everyday words before introducing academic language; (3) integrating literacy throughout instruction; (4) guiding students to become critical thinkers through an inquiry process; and finally (5) developing trusting relation...
A Flame Emission Interference in the Atomic Absorption Determination of Calcium

Calcium is reported to be the element most frequently determined by atomic absorption, and the nitrous oxide–acetylene flame is recommended for this determination. We wish to point out a condition in which the strong calcium atomic emission from this high temperature flame markedly reduces the sensitivity of the atomic absorption determination and causes bending of the absorption analytical curve.
The vital role of saliva as a mechanical sealant for suckling in the rat.

Abstract Rats deprived of submaxillary-sublingual saliva before the 10th day of postnatal age die of starvation, but they suck effectively if the submaxillary-sublingual ablation is done on the 13th day or later [2]. The parotids were not considered by Plagge. We show here that parotid parenchyma does not appear by light microscopic examination until the 10th–14th day. Submaxillary-sublingual removal before that time therefore removes all functional salivary tissue and the pup's failure to suck effectively is the result of complete desalivation. Parotid removal at any age is benign but reproduces the Plagge phenomenon when combined on the 13th–14th days with submaxillary-sublingual ablation. Saliva is therefore essential for feeding throughout the suckling period. It is supplied in sufficient amounts by only the submaxillary-sublingual complex before the 8th day and thereafter also by the parotids once their development has begun. Effective sucking is restored to the desalivate pup (submaxillary-sublingual removal on the 6th day) by periodic treatment of its lips with vaseline. The pup holds fast to the nipple shortly after the vaseline is applied and milk reappears in its stomach. Saliva therefore functions as a mechanical sealant of the pup's lips and mouth to the maternal nipple.
Gauss-Legendre principal value integration

As we attempt more sophisticated projects in science and engineering, the mathematical tools we apply to them also become more sophisticated. Because so few problems lend themselves to closed-form solution, we often need to convert formal definitions into practical numerical methods. One such problem deals with the principal value integral, which many students encounter in courses on functions of complex variables. However, the prospect of evaluating such a problem numerically might seem rather daunting; the subject remains outside the treatments of numerical quadrature found in treatises on numerical analysis. This article looks at a simple, efficient procedure for numerically evaluating the Cauchy principal value integral. I/sub /spl Delta// {=P/spl int//sub -/spl Delta///sup /spl Delta//[/spl rho/(t+x)/t]dt} is approximated by a Gauss-Legendre quadrature formula.
Adsorption of cyanogen chloride and hydrogen cyanide by activated and impregnated carbons

Abstract Equilibrium adsorption and desorption isotherm data at room temperature are reported for cyanogen chloride and hydrogen cyanide vapors on BPL grade activated carbon, ASC whetlerite and several ASB impregnated carbons. Isotherm data have been analyzed in terms of the Dubinin-Polanyi equation. The experimental affinity coefficients ( β ex ) for the vapors, with respect to chloroform, were determined from the slope of the Dubinin-Polanyi plot. The relative adsorptive capabilities of the adsorbents were assessed by comparing the theoretical affinity coefficient ( β th ) with β ex · β th was estimated assuming that physical adsorption is the dominant adsorption process. Cyanogen chloride shows about 20% higher adsorption than predicted on BPL activated carbon and about 30% higher than predicted on the ASB impregnated carbons. Hydrogen cyanide shows about 30% higher adsorption than predicted on BPL activated carbon and about 45% higher adsorption than predicted on the ASB impregnated carbons. In the case of ASC whetlerite, the adsorption of both vapors was much greater than predicted and the isotherms displayed a levelling-off trend in the low pressure region indicating strong retention through chemisorptive interactions. No unique β ex could be determined from the original isotherms. An attempt was made to separate the chemisorption contribution from the total adsorption, and thus assess β ex for the physical adsorption contribution.
A feasibility study of markerless fluoroscopic gating for lung cancer radiotherapy using 4DCT templates

A major difficulty in conformal lung cancer radiotherapy is respiratory organ motion, which may cause clinically significant targeting errors. Respiratory-gated radiotherapy allows for more precise delivery of prescribed radiation dose to the tumor, while minimizing normal tissue complications. Gating based on external surrogates is limited by its lack of accuracy, while gating based on implanted fiducial markers is limited primarily by the risk of pneumothorax due to marker implantation. Techniques for fluoroscopic gating without implanted fiducial markers (markerless gating) have been developed. These techniques usually require a training fluoroscopic image dataset with marked tumor positions in the images, which limits their clinical implementation. To remove this requirement, this study presents a markerless fluoroscopic gating algorithm based on 4DCT templates. To generate gating signals, we explored the application of three similarity measures or scores between fluoroscopic images and the reference 4DCT template: un-normalized cross-correlation (CC), normalized cross-correlation (NCC) and normalized mutual information (NMI), as well as average intensity (AI) of the region of interest (ROI) in the fluoroscopic images. Performance was evaluated using fluoroscopic and 4DCT data from three lung cancer patients. On average, gating based on CC achieves the highest treatment accuracy given the same efficiency, with a high target coverage (average between 91.9% and 98.6%) for a wide range of nominal duty cycles (20-50%). AI works well for two patients out of three, but failed for the third patient due to interference from the heart. Gating based on NCC and NMI usually failed below 50% nominal duty cycle. Based on this preliminary study with three patients, we found that the proposed CC-based gating algorithm can generate accurate and robust gating signals when using 4DCT reference template. However, this observation is based on results obtained from a very limited dataset, and further investigation on a larger patient population has to be done before its clinical implementation.
Compact flattop laser beam shaper using vectorial vortex

In this paper, we demonstrate a compact flattop beam shaper to realize two-dimensional flattop focus through generating a second order full Poincare beam. Liquid crystal material is used in the device as the voltage-dependent birefringent material to provide appropriate phase retardation modulation. The beam shaper is fabricated and tested. Experimental results show that high quality flattop profiles can be obtained with steep edge roll-off. The tolerance of different input beam sizes of the beam shaper is also verified in the experimental demonstration.
Health Education Needs Assessment in an HMO: A Case Study

Potential health education services for HMO subscribers are numerous and varied, ranging across the entire wellness to sickness spectrum. Because of cost consciousness and limited educational resources, careful needs assessment and selection of priorities are vital to the success of HMO health education efforts. The results of utilizing six needs assessment methodologies are presented in this case study. Consumer and provider involvement in the needs assessment process revealed five top priority health problems or opportunities for health education: membership education needs; overweight/obesity; self-care needs; hypertension; and smoking. These recommendations did not include perinatal and pediatric health education services as top priority needs, an outcome at variance with the results of the other needs assessment methodologies. This variance emphasizes the importance of employing multiple techniques in the needs assessment process. Problems in implementing various needs assessment methodologies are di...
SU-E-T-476: Quality Assurance for Gamma Knife Perfexion Using the Exradin W1 Plastic Scintillation Detector

Purpose: To perform dose profile and output factor measurements for the Exradin W1 plastic scintillation detector (PSD) for the Gamma Knife Perfexion (GKP) collimators in a Lucy phantom and to compare these values to an Exradin A16 ion chamber, EBT3 radiochromic film and treatment planning system (TPS) data. Methods: We used the Exradin W1 PSD which has a small volume, near-water equivalent sensitive element. It has also been shown to be energy independent. This new detector is manufactured and distributed by Standard Imaging, Inc. Measurements were performed for all three collimators (4 mm, 8 mm and 16 mm) for the GKP. The Lucy phantom with the PSD inserted was moved in small steps to acquire profiles in all three directions. EBT3 film was inserted in the Lucy phantom and exposed to a single shot for each collimator. Relative output factors were measured using the three detectors while profiles acquired with the PSD were compared to the ones measured with EBT3 radiochromic film. Results: Measured output factors relative to the largest collimator are as followsCollimator PS EBT3 A1616mm 1.000 1.000 1.0008mm 0.892 0.881 0.8834mm 0.795 0.793 0.727 The nominal (vendor) OFs for GKP are 1.000, 0.900, and 0.814, for collimators 16 mm, 8 mm and 4 mm, respectively. There is excellent agreement between all profiles measured with the PSD and EBT3 as well as with the TPS data provided by the vendor. Conclusion: Output factors measured with the W1 were consistent with the ones measured with EBT3 and A16 ion chamber. Measured profiles are in excellent agreement. The W1 detector seems well suited for beam QA for Gamma Knife due to its dosimetric characteristics. Sam Beddar would like to disclose a NIH/NCI SBIR Phase II grant (2R44CA153824-02A1) with Standard Imaging, Title: “Water-Equivalent Plastic Scintillation Detectors for Small Field Radiotherapy”
X-ray phototherapy for canine brain masses

Brain masses diagnosed in 47 pet dogs as tumors by CT scans, and confirmed in 12 dogs by necropsies, were injected with iodinated contrast media and treated by a modified CT scanner, the CTRx. Twenty-six dogs that received six or more weekly treatments of about 5.6 Gy per fraction, of which about 25% was contributed by radiation from the iodine, for a median total dose of 39 Gy, had a median survival of 230 days. This compares well with the 150 days reported for 25 dogs given 46-48 Gy of cobalt-60 radiation to the whole brain, and is significantly greater than the 6 to 13 days in untreated historic controls.
Sample collection procedures for laboratory analysis in the United States soil survey program

Abstract The United States National Cooperative Soil Survey Program has prepared soil maps for much of the country. Both field and laboratory data are used to design map units and provide supporting information for scientific documentation and predictions of soil behavior. Coordination of mapping, sampling site selection, and sample collection in this program contributes to the quality assurance process for laboratory characterization. Requisites to successful laboratory analysis of soils occur long before the sample is analyzed. In the field, these requisites include site selection, descriptions of site and soil pedon, and careful sample collection. A complete description of the sampling site not only provides a context for the various soil properties determined, but it is also a useful tool in the evaluation and interpretation of the soil analytical results. Landscape, landform, and pedon documentation of the sampling site serves as a link in a continuum of analytical data, sampled horizon, pedon, lands...
Bilateral vulvar basal cell carcinomata

Vulvar basal cell carcinoma is rare, accounting for less than 5% of vulvar neoplasms. There is great variation in the clinical appearance of this neoplasm, which occurs most commonly in older women. Metastasis seldom occurs, but the tumor may extend deeply into local tissues. We report the first case of bilateral vulvar basal cell carcinomata in a 66-year-old woman who had received radiotherapy for urethral carcinoma 35 years earlier. Both tumors were treated with Mobs micrographic surgery and have not recurred after 13 years.
An improved rapid method for heteronuclear two-dimensional Jspectroscopy

Abstract Improved two-dimensional heteronuclear J spectroscopy pulse sequences with fast restoration of the z magnetization, multiple refocusing, and acquisition of both halves of the spin echos are described. The experimental results show that these methods can effectively enhance the signals of the 2-D J spectra.
Spatial language influences memory for spatial scenes

Does language influence recognition for spatial scenes? In Experiments 1 and 2, participants viewed ambiguous pictures, with or without spatial sentences. In a yes—no recognition task, only the spatial sentences group made more false alarms toward the center of the spatial category than in the other direction; three other comparison groups showed no such tendency. This shift toward the core of the semantic category suggests that spatial language interacted with perceptual information during encoding. In Experiment 3, we varied the materials to test the interactive encoding account against a separate encoding account in which separately stored sentences are accessed during picture recognition. The results support the interactive encoding account in which spatial language influences the encoding and memory of spatial relations.
Genetic Determinants of Intrinsic Colistin Tolerance in Acinetobacter baumannii

Acinetobacter baumannii is a leading cause of multidrug-resistant infections worldwide. This organism poses a particular challenge due to its ability to acquire resistance to new antibiotics through adaptation or mutation. This study was undertaken to determine the mechanisms governing the adaptability of A. baumannii to the antibiotic colistin. Screening of a transposon mutant library identified over 30 genes involved in inducible colistin resistance in A. baumannii. One of the genes identified was lpsB, which encodes a glycosyltransferase involved in lipopolysaccharide (LPS) synthesis. We demonstrate that loss of LpsB function results in increased sensitivity to both colistin and cationic antimicrobial peptides of the innate immune system. Moreover, LpsB is critical for pathogenesis in a pulmonary model of infection. Taken together, these data define bacterial processes required for intrinsic colistin tolerance in A. baumannii and underscore the importance of outer membrane structure in both antibiotic resistance and the pathogenesis of A. baumannii.
A Case of Schwannoma of the Nasal Tip: Resection Using an External Rhinoplasty Approach

Schwannoma is a benign tumor originating from the peripheral nerve sheath. A 16-year-old man have experienced progressive swelling of the nasal tip over 4 years. Computed tomography scan showed a 2.5 cm sized soft tissue density at the nasal tip. It distorted and dislocated the lower lateral cartilage. The mass was resected using an external rhinoplasty approach. The nasal tip was reconstructed by tip surgery and the soft tissue defect under the skin due to mass was filled with autologous dermal graft. The pathologic diagnosis was a schwannoma. A nasal tip schwannoma is extremely rare. Here, we present and discuss the clinical and surgical aspects of schwannoma arising on the nasal tip. � Korean J Otorhinolaryngol-Head Neck Surg 2011;54:356-9 Key WordsZZSchwannomaㆍNoseㆍRhinoplasty.
Outlier Detection and Clustering by Partial Mixture Modeling

Clustering algorithms based upon nonparametric or semiparametric density estimation are of more theoretical interest than some of the distance-based hierarchical or ad hoc algorithmic procedures. However density estimation is subject to the curse of dimensionality so that care must be exercised. Clustering algorithms are sometimes described as biased since solutions may be highly influenced by initial configurations. Clusters may be associated with modes of a nonparametric density estimator or with components of a (normal) mixture estimator. Mode-finding algorithms are related to but different than gaussian mixture models. In this paper, we describe a hybrid algorithm which finds modes by fitting incomplete mixture models, or partial mixture component models. Problems with bias are reduced since the partial mixture model is fitted many times using carefully chosen random starting guesses. Many of these partial fits offer unique diagnostic information about the structure and features hidden in the data. We describe the algorithms and present some case studies.
Detection of Ehrlichia chaffeensis DNA in Amblyomma americanum Ticks in Connecticut and Rhode Island

Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis, is transmitted by Amblyomma americanum ticks, which are most abundant in the southern United States. Because serologic evidence suggests that residents of Connecticut are exposed to E. chaffeensis, A. americanum ticks were collected in Connecticut and Rhode Island for PCR analysis to detect E. chaffeensis DNA. Eight of 106 (7.6%) A. americanum ticks from Connecticut and 6 of 52 (11.5%) from Rhode Island contained E. chaffeensis DNA. Thus, E. chaffeensis is present in ticks in southern New England and transmission of E. chaffeensis may occur there.
Classification via the Shadow Region in SAR Imagery

The use of a target's shadow in synthetic aperture radar (SAR) imaging has garnered much attention for automated target recognition (ATR) applications. A technique of hidden Markov modeling (HMM) of the shadow profile is developed here. The basic HMM technique is refined using ensemble averaging, mission-based model selection criteria, multi-look scenarios, and data fusion. The algorithms are tested using DARPA's moving and stationary target acquisition and recognition (MSTAR) data. One of the drawbacks of using SAR shadows is that there exist certain, yet limited, target-radar configurations where the shadow simply does not robustly provide discriminatory target information. This limitation, however, can be easily overcome by imaging a target at multiple poses. With two orthogonal looks, the shadow-only classifier was seen to have an average classification performance of over 90% for a five target system. Additionally, the output of the shadow-only classifier is illustrated to be independent of a scattering center based classifier. All of the results indicate that the shadows provide useful discriminatory information that can be used to advance recognition capabilities in SAR ATR applications.
Extending Multicast Communications by Hybrid Overlay Network

Recently scalable streaming applications have been developed by the new emerging networking technologies. One interesting challenge is how to build an efficient and reliable network topology over heterogeneous network systems. In this paper, we argue that hybrid network overlay, via both IP multicast and overlay mesh multicast, is an important technology for group communications. In this paper, we propose a hybrid network overlay construction with three performance goals: high performance (low end-to-end transmission latency, high bandwidth mesh overlay links), low end-to-end hop count and high reliability. This paper compares the performance penalties from IP multicast, overlay multicast and hybrid overlay multicast via various topology simulations.
Postkeratoplasty keratoconus in a nonkeratoconus patient.

Abstract PURPOSE: To determine whether postkeratoplasty keratoconus is caused by a recurrence of the host disease or transferred from the donor. METHODS: Penetrating keratoplasty was performed on the right eye of a 73-year-old woman with pseudophakic bullous keratopathy; her other eye was normal. After keratoplasty, visual acuity decreased secondary to the appearance of irregular astigmatism, central corneal thinning, and stromal striae in the graft. A repeat keratoplasty was performed. Clinical corneal topographic analysis and histopathologic studies were performed. RESULTS: Clinical findings and histopathology of the corneal graft were consistent with keratoconus. The second graft has remained clear for 2 years without signs of keratoconus. CONCLUSION: Classic keratoconus developed in a corneal graft in a patient without preexisting keratoconus. This supports the theory that postkeratoplasty keratoconus may be secondary to transfer of the disease from the donor.
Involvement of Raft-Like Plasma Membrane Domains of Entamoeba histolytica in Pinocytosis and Adhesion

Lipid rafts are highly ordered, cholesterol-rich, and detergent-resistant microdomains found in the plasma membrane of many eukaryotic cells. These domains play important roles in endocytosis, secretion, and adhesion in a variety of cell types. The parasitic protozoan Entamoeba histolytica, the causative agent of amoebic dysentery, was determined to have raft-like plasma membrane domains by use of fluorescent lipid analogs that specifically partition into raft and nonraft regions of the membrane. Disruption of raft-like membrane domains in Entamoeba with the cholesterol-binding agents filipin and methyl-beta-cyclodextrin resulted in the inhibition of several important virulence functions, fluid-phase pinocytosis, and adhesion to host cell monolayers. However, disruption of raft-like domains did not inhibit constitutive secretion of cysteine proteases, another important virulence function of Entamoeba. Flotation of the cold Triton X-100-insoluble portion of membranes on sucrose gradients revealed that the heavy, intermediate, and light subunits of the galactose-N-acetylgalactosamine-inhibitible lectin, an important cell surface adhesion molecule of Entamoeba, were enriched in cholesterol-rich (raft-like) fractions, whereas EhCP5, another cell surface molecule, was not enriched in these fractions. The subunits of the lectin were also observed in high-density, actin-rich fractions of the sucrose gradient. Together, these data suggest that pinocytosis and adhesion are raft-dependent functions in this pathogen. This is the first report describing the existence and physiological relevance of raft-like membrane domains in E. histolytica.
Exercise and the obese child

Abstract Obesity in children has been associated with lower levels of physical activity and fitness. Physical activity and exercise are essential elements in obesity treatment. Consensus recommendations for obesity prevention recommend that children and adolescents accumulate 60 minutes or more of at least moderate physical activity daily. In addition to obesity, risk for decreased physical activity also includes being an ethnic minority, living in poverty, having a disability, living in an apartment or public housing, adverse climate, and perceived or actual lack of neighborhood safety. The combination of decreased fitness and decreased physical activity can magnify metabolic changes. Regular physical activity has also been shown to lessen the burden of obesity-related comorbidities, including reductions in blood pressure, increased insulin sensitivity, and decrease in hepatomegaly. Exercise prescriptions for obese children should involve family support, activities which are doable, fun and develop participatory skills. Children with congenital heart disease are also at risk for obesity and represent a group of children that requires focused attention on obesity prevention and treatment.
Optimal phased-array combination for spectroscopy

A method for making weighted linear combinations of the spectra acquired by a phased-array coil is described. Unlike most previous combination methods, no special reference points in the data are chosen to represent the coil weights. Instead, all the data points are used, which results in optimal signal-to-noise ratio more reliable estimation. The method uses singular value decomposition to identify the coil weights and extract the principal component of variation in the signal. Subsequent processing of the combined signal (e.g., Fourier transform, baseline correction, phasing) may proceed as per a single coil acquisition.
Evidence for a global seismic-moment release sequence

Temporal clustering of the larger earthquakes (foreshock-mainshock-aftershock) followed by relative quiescence (stress shadow) are characteristic of seismic cycles along plate boundaries. A global seismic-moment release history, based on a little more than 100 years of instrumental earthquake data in an extended version of the catalog of Pacheco and Sykes (1992), illustrates similar behavior for Earth as a whole. Although the largest earthquakes have occurred in the circum-Pacific region, an analysis of moment release in the hemisphere antipodal to the Pacific plate shows a very similar pattern. Monte Carlo simulations confirm that the global temporal clustering of great shallow earthquakes during 1952–1964 at M ≥ 9.0 is highly significant (4% random probability) as is the clustering of the events of M ≥ 8.6 (0.2% random probability) during 1950–1965. We have extended the Pacheco and Sykes (1992) catalog from 1989 through 2001 using Harvard moment centroid data. Immediately after the 1950–1965 cluster, significant quiescence at and above M 8.4 begins and continues until 2001 (0.5% random probability). In alternative catalogs derived by correcting for possible random errors in magnitude estimates in the extended Pacheco–Sykes catalog, the clustering of M ≥ 9 persists at a significant level. These observations indicate that, for great earthquakes, Earth behaves as a coherent seismotectonic system. A very-large-scale mechanism for global earthquake triggering and/or stress transfer is implied. There are several candidates, but so far only viscoelastic relaxation has been modeled on a global scale.
A microfabricated carbon dioxide sensor for portable applications

The reliable detection of carbon dioxide (CO 2 ) emissions is a key step towards the ability to mitigate CO 2 levels in the atmosphere. At present, many CO 2 sensors exist, but they all require on the order of watts of power, therefore, they are not suitable for long term unattended operation. In this paper, we present a new design for a microfabricated CO 2 sensor that operates at room temperature with very low power input. The device uses the selective adsorption of CO 2 in a room temperature ionic liquid (RTIL) followed by an electrochemical reaction at a gold electrode to detect the presence of CO 2 . We find that the device is able to measure normal atmospheric levels of CO 2 with high reliability using less than 10 µW of power. This advance will enable a new class of portable CO 2 sensors to be constructed.
Generation and Surface Localization of Intact M Protein in Streptococcus pyogenes Are Dependent on sagA

The M protein is an important surface-located virulence factor of Streptococcus pyogenes, the group A streptococcus (GAS). Expression of M protein is primarily controlled by Mga, a transcriptional activator protein. A recent report suggested that the sag locus, which includes nine genes necessary and sufficient for production of streptolysin S, another GAS virulence factor, is also needed for transcription of emm, encoding the M protein (Z. Li, D. D. Sledjeski, B. Kreikemeyer, A. Podbielski, and M. D. Boyle, J. Bacteriol. 181:6019-6027, 1999). To investigate this in more detail, we constructed an insertion-deletion mutation in sagA, the first gene in the sag locus, in the M6 strain JRS4. The resulting strain, JRS470, produced no detectable streptolysin S and showed a drastic reduction in cell surface-associated M protein, as measured by cell aggregation and Western blot analysis. However, transcription of the emm gene was unaffected by the sagA mutation. Detailed analysis with monoclonal antibodies and an antipeptide antibody showed that the M protein in the sagA mutant strain was truncated so that it lacks the C-repeat region and the C-terminal domain required for anchoring it to the cell surface. This truncated M protein was largely found, as expected, in the culture supernatant. Lack of surface-located M protein made the sagA mutant strain susceptible to phagocytosis. Thus, although sagA does not affect transcription of the M6 protein gene, it is needed for the surface localization of this important virulence factor.
About Clapeyron’s Theorem in Linear Elasticity

We examine some elementary interpretations of the classical theorem of Clapeyron in linear elasticity theory. As we show, a straightforward application of this theorem in the purely mechanical setting leads to an apparent paradox which can be resolved by referring either to dynamics or to thermodynamics. These richer theories play an essential part in understanding the physical significance of this theorem.
Enhancing web accessibility

This demonstration will illustrate the key technical and user interface aspects of the Web Adaptation Technology. Various transformations underlying the system will be shown that illustrate how this approach enables a wide range of users with reduced visual, cognitive, and motor abilities to access a large proportion of Web pages using a standard browser.
Transient Behavior of Inclusion Chemistry, Shape, and Structure in Fe-Al-Ti-O Melts: Effect of Titanium/Aluminum Ratio

During ladle processing of interstitial-free (IF) steel melts, it is possible for transient titanium-containing oxides to be formed if the local titanium/aluminum (Ti/Al) ratio is locally and temporarily increased after aluminum killing. The phase stability diagrams suggest that if the Ti/Al ratio is increased, then Al2TiO5 and/or a liquid Al-Ti-O region can become stable, and eventually at even higher Ti/Al ratios, Ti3O5 becomes stable. In this study, the Ti/Al ratio was successively altered to investigate (1) how the inclusions evolved after titanium addition to aluminum-killed iron melts and (2) whether the inclusions present after sufficient time were those predicted by thermodynamics. When the Ti/Al ratio was maintained at 1/4, such that Al2O3 is the only thermodynamically stable oxide, the results show that transient titanium-containing oxides exist temporarily after titanium addition, but with time, the predominant inclusion was Al2O3, which would generate little shape change and produce transient stage inclusions with less titanium contents. When the Ti/Al ratio was increased to 1/1 (Al2O3 still being the only thermodynamically stable oxide), the results show a more distinct increase in the titanium content of the transient inclusions. The transient reaction was, in this case, accompanied by an irreversible shape change from spherical to irregular inclusions. When the Ti/Al ratio in the melt was increased to 15/1 within the Al2TiO5 stable phase region, the inclusion population evolved from spherical-dominant ones to irregular ones. It was found that the final inclusion chemistry has more titanium but less aluminum content compared with the expected from the Al2TiO5 chemistry. Besides, the transmission electron microscopy (TEM) results showed the existence of Ti2O. When the Ti/Al ratio in the melt was increased such that Ti3O5 is the thermodynamically stable inclusion (Ti/Al ratio of 75/1 or ∞), the inclusions evolved after titanium addition toward TiOx inclusions, which is accompanied by a shape change from spherical to irregular. The TEM results revealed and confirmed the existence of metastable Ti2O besides the thermodynamically stable Ti3O5, and it was consistent with the results based on oxidation studies of thin layers of titanium with Al2O3 substrate. It was discovered that Ti2O has the tendency of transforming into the thermodynamically stable phase Ti3O5 under certain conditions.
An integrated mobile satellite broadcast, paging, communications and navigation system

The design of an integrated mobile satellite broadcast, paging, communications, and navigation system is described. Ku-band RadioSat ground stations will broadcast digital audio signals and data packets (including alphanumeric pages and group cells) to mobiles through a satellite to be launched in 1993. Each mobile radio will simultaneously receive L-band digital audio and data broadcasts from the satellite and L-band navigation broadcasts from the Global Positioning Systems (GPS) through a common omnidirectional mobile antenna and receiver front end. RadioSat mobile radios will use GPS broadcasts and differential corrections sent through the satellite to navigate with 2-m accuracy. With optional transmitters, RadioSat mobile radios can support two-way voice and data communications. >