bluuebunny/crossref_metadata_2025 huggingface dataset:
Word-length and context effects on the acoustics of /ai/
Authors: Narayan Chandan R.
Published: September 2013

The acoustics of American English /ai/ are investigated. This study investigated whether speakers maintain an invariant slope of the F2 transition across the vowel shortening effects of increased word length and the vowel lengthening effects of following obstruent voicing. Six speakers recorded minimal /ai/ triplets varying in word length and post-vocalic place and voicing (i.e., hide, Heidi, Heidelberg; hype, hyper, hyperness). Analysis of both temporal and spectral characteristics revealed systematic effects of word length and voicing. With increasing word length /ai/ duration significantly decreased across all variables, except in voiceless contexts where there was not a significant decrease from two- to three-syllable words. Before voiced obstruents F2 transition onset increased significantly from one- to two-syllable words with offset frequencies remaining stable. In the three-syllable word condition, the F2 transition offset dropped significantly. Importantly, F2 transition slope remained stable across word lengths, which mirrors earlier findings of constant F2 slope across different speaking rates (Gay, 1968; Miller et al., 1994). However, F2 transition slope was not constant across voicing conditions, being significantly higher before voiceless obstruents than before voiced obstruents. Findings will be compared with earlier work on diphthong acoustics across temporal manipulations.
Tabu evaluation in geoacoustic inversion
Authors: Michalopoulou Zoi-Heleni
Published: September 2013

Tabu optimization has recently been proposed as a tool for geoacoustic inversion. Tabu introduces a structured use of memory in the exploration of the search space, a novel element in inversion. For performance evaluation the technique is applied to Workshop 97 test cases. These cases provide a good framework for the validation of the new approach, since results from the application of several optimization schemes to these synthetic data sets exist in the literature. Tabu is evaluated on narrow-band and broadband data in the estimation of various combinations of geoacoustic parameters. The method is successful in accurate parameter estimation and requires relatively few forward model calculations. Tabu is also evaluated in a rotated coordinate framework, in an attempt to exploit parameter correlations for faster identification of the global maximum. [Work supported by ONR.]
Estimating the precision error in hearing protector ratings
Authors: Murphy William J. , Franks John R. , Shaw Peter B.
Published: September 2013

The variance associated with hearing protector rating methods is derived for the Noise Reduction Rating, Noise Reduction Rating Subject Fit, and Single Number Rating methods. Real-ear attenuation at threshold (REAT) data have an error that is a function of stimulus frequency, protector fit, protector type, and the subject performance during occluded and unoccluded threshold estimation. In addition to the error associated with conducting the REAT tests, there is an additional error that results from applying the rating to a noise spectrum different from the spectrum used to derive the rating. For this paper, a distinction is made between the accuracy of the rating and the precision of the rating. The precision is an inherent property of the subject panel, protector type and fit, and the frequencies tested. The accuracy will be attributed to the application of the rating to an arbitrary noise. [Portions of work supported by the U.S. EPA IA 75090527.]
The influence of target-masker similarity on across-ear interference in dichotic listening
Authors: Brungart Douglas , Simpson Brian
Published: September 2013

In most dichotic listening tasks, the comprehension of a target speech signal presented in one ear is unaffected by the presence of irrelevant speech in the opposite ear. However, recent results have shown that contralaterally presented interfering speech signals do influence performance when a second interfering speech signal is present in the same ear as the target speech. In this experiment, we examined the influence of target-masker similarity on this effect by presenting ipsilateral and contralateral masking phrases spoken by the same talker, a different same-sex talker, or a different-sex talker than the one used to generate the target speech. The results show that contralateral target-masker similarity has the greatest influence on performance when an easily segregated different-sex masker is presented in the target ear, and the least influence when a difficult-to-segregate same-talker masker is presented in the target ear. These results indicate that across-ear interference in dichotic listening is not directly related to the difficulty of the segregation task in the target ear, and suggest that contralateral maskers are least likely to interfere with dichotic speech perception when the same general strategy could be used to segregate the target from the masking voices in the ipsilateral and contralateral ears.
Anterior tongue and jaw movement in sVd words
Authors: McGowan Richard S.
Published: September 2013

The relations between jaw and tongue movements were examined using words of the form sVd for eight different speakers from the X-Ray Microbeam Speech Production Database. Measurements were examined at the maximum speeds during the release and during the closure of the tongue blade and tongue body. For nonhigh vowels the tongue blade traveled in the same direction as the jaw during release, and, to a lesser extent, the same was true during closure. Further, the magnitude of the projection of the tongue blade velocity onto the direction of the jaw movement was often large compared with the speed of the jaw. There was less consistency in the relation between tongue body and jaw movement. These results indicate that the jaw and tongue movements are not rigidly coupled. Rather the jaw, which can provide a hard boundary for the tongue, is getting out of the tongue’s way during release and following the tongue on closure for subsequent bracing. [Work supported by Grant NIDCD-01247 to CReSS LLC.]
Investigation of a combined seismic, radar, and induction sensor for landmine detection
Authors: Scott Waymond , Kim Kangwook , Larson Gregg
Published: September 2013

An experimental system to collect co-located ground penetrating radar (GPR), electromagnetic induction (EMI), and seismic data was developed to investigate the benefits of the fusion of these sensors. In the experiments, a range of mines and clutter objects were buried at various depths in the sandbox at Georgia Tech. Multiple burial scenarios were investigated with a variety of antipersonnel and antitank mines and typical clutter objects. The seismic system used in these experiments is an extension of our existing seismic mine detection system. The system uses electrodynamic shakers to generate a seismic wave which propagates across the simulated minefield, and a specially designed radar is used to measure the displacement of the surface caused by the seismic wave. The GPR makes use of modified resistive-vee antennas and operates over the frequency range of 500 MHz to 8 GHz. These antennas are very clean in that they have very little self-clutter and very low radar cross section to lessen the reflections between the ground and the antennas. The EMI sensor collects broadband data (300 Hz to 100 kHz) so that the relaxation frequencies of the buried targets can be used to aid discrimination. [Work supported by ARO.]
Speech perception in gated noise: the effects of spectral/temporal resolution and auditory integration
Authors: Jin Su-Hyun , Nelson Peggy B.
Published: September 2013

The current investigation examined differences between hearing impaired (HI) listeners and normal-hearing listeners (NH) in the amount of masking release (MR) for sentence recognition and syllable identification tasks when they listened in modulated noise. HI and NH listeners’ performance was compared when the performance levels of the two groups were equal in steady noise and in quiet. The relationships between the amount of MR to hearing threshold and suprathreshold abilities of forward masking, auditory filter bandwidth, and auditory stream segregation/integration were also investigated. To compensate for reduced hearing sensitivity for HI listeners, the spectrum levels of both speech and noise were adjusted based on the individual hearing loss. There was no significant performance difference between NH and HI groups in steady noise and in quiet. However, the amount of MR for sentences and for CV syllables was significantly reduced for HI listeners. For sentence recognition, the amount of MR seemed to be more related to hearing sensitivity for low-to-mid frequencies and the characteristics of auditory filters. Performance for gated sentence recognition was also strongly correlated with sentence recognition in gated noise. In contrast, forward masking thresholds appear to be the main contributor to the amount of MR for syllable recognition.
Eigenfunction analysis of stochastic backscatter for aberration correction in medical ultrasound imaging
Authors: Varslot Trond , Mo Eirik , Krogstad Harald , Angelsen Bjo/rn
Published: September 2013

A filter for aberration correction in medical ultrasound imaging is presented. The filter is optimal in the sense of maximizing the expected energy in a modified beamformer output of the received acoustic backscatter. The situation considered is frequently found in applications when imaging organs through a body wall: aberration is introduced in a layer close to the transducer, and acoustic backscatter from a scattering region behind the body wall is measured at the transducer surface. The scattering region consists of scatterers randomly distributed with very short correlation length compared to the acoustic wave length of the transmit pulse. The scatterer distribution is therefore assumed to be δ-correlated. Theoretical considerations imply that maximizing the expected energy in a modified beamformer output signal naturally leads to eigenfunctions of a Fredholm integral operator, where the associated kernel function is a spatial correlation function of the received stochastic signal. Aberration characterization and aberration correction have been studied for simulated data constructed to mimic aberration introduced by the abdominal wall. The results compare well with what is obtained using a diffraction limited time-reversal filter based on simulated point source data.
Frequency-wavenumber processing for infrasound distributed arrays
Authors: Costley R. Daniel , Frazier W. Garth , Dillion Kevin , Picucci Jennifer R. , Williams Jay E. , McKenna Mihan H.
Published: September 2013

The work described herein discusses the application of a frequency-wavenumber signal processing technique to signals from rectangular infrasound arrays for detection and estimation of the direction of travel of infrasound. Arrays of 100 sensors were arranged in square configurations with sensor spacing of 2 m. Wind noise data were collected at one site. Synthetic infrasound signals were superposed on top of the wind noise to determine the accuracy and sensitivity of the technique with respect to signal-to-noise ratio. The technique was then applied to an impulsive event recorded at a different site. Preliminary results demonstrated the feasibility of this approach.
Influence of state and compressibility on liquefied strength of sands
Authors: Sadrekarimi Abouzar
Published: September 2013

Critical-state soil mechanics is a useful framework to understand sand behavior. In this paper, a relationship is developed for estimating undrained critical shear strength of sands based on the critical-state framework. The application of this relationship is demonstrated by comparison with laboratory test results and sand liquefied strength from field liquefaction flow failure case histories. Using this relationship, the effects of effective stress variation and density on undrained critical shear strength are studied for different combinations of critical-state line parameters corresponding to several reference sands. The parametric study indicates that depending on sand void ratio, undrained critical shear strength may increase, remain the same or decrease as sand shearing–compressibility (represented by the slope of the critical-state line) increases. The underlying mechanisms of field failures in dense sands and reverse behavior of compressible sands are explained through this relationship. It is suggested that the critical-state parameter alone is insufficient for describing the behavior of liquefiable sands and sand shearing–compressibility should be also taken into account for estimating undrained shear strength corresponding to the changes in density and effective confining stress.
HOW LONG COULD/SHOULD BE THE RESTORATION TIME FOR HIGH AVAILABILITY?
Authors: SUHIR E.
Published: September 2013

A simple physically meaningful predictive model is developed for the assessment of the acceptable duration of the repair (restoration) time to keep the system's availability level sufficiently high. The role of the random nature of the restoration time is taken into account. High availability can be achieved by making large, after a malfunction is detected, the ratio of the intensity of restorations to the failure rate. It is shown how this way to go could be effectively quantified. The general concept is illustrated by a numerical example.
MULTI-WINDING TRANSFORMER-BASED DIODE CLAMPING MULTILEVEL INVERTER, EXPERIMENTAL RESULTS
Authors: ESFANDIARI EHSAN , MESRINEJAD FARHAD , MARIUN NORMAN BIN
Published: September 2013

The feasibility of a staircase-output, diode clamping multilevel inverter based on multiwinding transformer is investigated through experimental results including: output voltage and current waveforms under resistive and inductive loads and the THD. The 2.5 kW, 7-level prototype of the constructed configuration proves the ability to act as an inverter under resistive and inductive loads and generates outputs with 2.1–11.5% of THD and 92.5% of peak efficiency. At last, a table of comparison with the closest topology is brought.
A RAID-BASED SECURE AND FAULT-TOLERANT MODEL FOR CLOUD INFORMATION STORAGE
Authors: FITCH DANIEL , XU HAIPING
Published: September 2013

Cloud computing allows for access to ubiquitous data storage and powerful computing resources through the use of web services. There are major concerns, however, with data security, reliability, and availability in the cloud. In this paper, we address these concerns by introducing a novel security mechanism for secure and fault-tolerant cloud information storage. The information storage model follows the RAID (Redundant Array of Independent Disks) concept by considering cloud service providers as independent virtual disk drives. As such, the model utilizes multiple cloud service providers as a cloud cluster for information storage, and a service directory for management of the cloud clusters including service query, key management, and cluster restoration. Our approach not only supports maintaining the confidentiality of the stored data, but also ensures that the failure or compromise of an individual cloud provider in a cloud cluster will not result in a compromise of the overall data set. To ensure a correct design, we present a formal model of the security mechanism using hierarchical colored Petri nets (HCPN), and verify some key properties of the model using model checking techniques.
IRRATIONALITY OF LAMBERT SERIES ASSOCIATED WITH A PERIODIC SEQUENCE
Authors: LUCA FLORIAN , TACHIYA YOHEI
Published: September 2013

Let q be an integer with |q| > 1 and {an}n≥1 be an eventually periodic sequence of rational numbers, not identically zero from some point on. Then the number [Formula: see text] is irrational. In particular, if the periodic sequences [Formula: see text] of rational numbers are linearly independent over ℚ, then so are the following m + 1 numbers: [Formula: see text] This generalizes a result of Erdős who treated the case of m = 1 and [Formula: see text]. The method of proof is based on the original approaches of Chowla and Erdős, together with some results about primes in arithmetic progressions with large moduli of Ahlford, Granville and Pomerance.
Wrinkled-graphene wrapped silicon nanoparticles synthesized through charged colloidal assembly for enhanced battery performance
Authors: Li Hai , Lu Chunxiang , Ma Canliang , Zhang Baoping
Published: September 2013

Elastic composite of wrinkled graphene sheets and Si nanoparticles has been prepared through engineering charged Si nanoparticles capping with 3-aminopropyl triethoxysilane and graphene oxide in colloidal state. In the composite, the Si nanoparticles are uniformly wrapped by the graphene sheets. When used as an anode for lithium-ion batteries, the as-obtained material exhibits high Coulombic efficiency, good cycling stability of 1044 mAh g-1 at a current density of 200 mA g-1 after 100 cycles, and superior rate capability. Such excellent electrochemical performance should be attributed to the wrinkled graphene sheets, which not only buffer volume expansion of Si nanoparticles during the cycling but also act as electrical conducting pathway.
Genomic Imprinting: Insights From Plants
Authors: Gehring Mary
Published: September 2013

Imprinted gene expression—the biased expression of alleles dependent on their parent of origin—is an important type of epigenetic gene regulation in flowering plants and mammals. In plants, genes are imprinted primarily in the endosperm, the triploid placenta-like tissue that surrounds and nourishes the embryo during its development. Differential allelic expression is correlated with active DNA demethylation by DNA glycosylases and repressive targeting by the Polycomb group proteins. Imprinted gene expression is one consequence of a large-scale remodeling to the epigenome, primarily directed at transposable elements, that occurs in gametes and seeds. This remodeling could be important for maintaining the epigenome in the embryo as well as for establishing gene imprinting.
Sea Ice Ecosystems
Authors: Arrigo Kevin R.
Published: September 2013

Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.
Engineered Botulinum Neurotoxins as New Therapeutics
Authors: Masuyer Geoffrey , Chaddock John A. , Foster Keith A. , Acharya K. Ravi
Published: September 2013

Botulinum neurotoxins (BoNTs) cause flaccid paralysis by inhibiting neurotransmission at cholinergic nerve terminals. Each BoNT consists of three domains that are essential for toxicity: the binding domain, the translocation domain, and the catalytic light-chain domain. BoNT modular architecture is associated with a multistep mechanism that culminates in the intracellular proteolysis of SNARE (soluble N-ethylmaleimide-sensitive-fusion-protein attachment protein receptor) proteins, which prevents synaptic vesicle exocytosis. As the most toxic proteins known, BoNTs have been extensively studied and are used as pharmaceutical agents to treat an increasing variety of disorders. This review summarizes the level of sophistication reached in BoNT engineering and highlights the diversity of approaches taken to utilize the modularity of the toxin. Improved efficiency and applicability have been achieved by direct mutagenesis and interserotype domain rearrangement. The scope of BoNT activity has been extended to nonneuronal cells and offers the basis for novel biomolecules in the treatment of secretion disorders.
Isomorphisms on Weighed Banach Spaces of Harmonic and Holomorphic Functions
Authors: Jordá Enrique , Zarco Ana María
Published: September 2013

For an arbitrary open subsetU⊂ℝdorU⊆ℂdand a continuous functionv:U→]0,∞[we show that the spacehv0(U)of weighed harmonic functions is almost isometric to a (closed) subspace ofc0, thus extending a theorem due to Bonet and Wolf for spaces of holomorphic functionsHv0(U)on open setsU⊂ℂd. Inspired by recent work of Boyd and Rueda, we characterize in terms of the extremal points of the dual ofhv0(U)whenhv0(U)is isometric to a subspace ofc0. Some geometric conditions on an open setU⊆ℂdand convexity conditions on a weightvonUare given to ensure that neitherHv0(U)norhv0(U)are rotund.
Synthesis of Pyrroloquinones via a CAN Mediated Oxidative Free Radical Reaction of 1,3‐Dicarbonyl Compounds with Aminoquinones
Authors: Nguyen Thao , Nadkarni Dwayaja , Dutta Shilpa , Xu Su , Kim Sanghun , Murugesan Srinivasan , Velu Sadanandan
Published: September 2013

Pyrroloquinone ring systems are important structural units present in many biologically active molecules including a number of marine alkaloids. For example, they are found in a series of marine metabolites, such as tsitsikammamines, zyzzyanones, wakayin, and terreusinone. Several of these alkaloids have exhibited antimicrobial, antimalarial, antifungal, antitumor, and photoprotecting activities. Synthesis of pyrroloquinone unit is the key step in the synthesis of many of these important organic molecules. Here, we present a ceric (IV) ammonium nitrate (CAN) mediated oxidative free radical cyclization reaction of 1,3‐dicarbonyl compounds with aminoquinones as a facile methodology for making various substituted pyrroloquinones. 1,3‐dicarbonyl compounds used in this study are ethyl acetoacetate, acetylacetone, benzoyl acetone, and N,N‐dimethyl acetoacetamide. The aminoquinones used in this study are 2‐(benzylamino)naphthalene‐1,4‐dione and 6‐(benzylamino)‐1‐tosyl‐1H‐indole‐4,7‐dione. The yields of the synthesized pyrroloquinones ranged from 23–91%.
Gastroesophageal Reflux Disease Relief in Patients Treated with Rabeprazole 20 mg versus Omeprazole 20 mg: A Meta-Analysis
Authors: Xia X. M. , Wang H.
Published: September 2013

Background. Randomized controlled trials (RCTs) have been conducted comparing the efficacy of rabeprazole 20 mg or omeprazole 20 mg once daily for patients with erosive gastroesophageal reflux disease (GERD). Until now, no study has synthesized all available data examining this issue.Method. Medline, Embase, and the Cochrane central register of controlled trials were searched (through December 2012). Eligible RCTs recruited adults with erosive GERD and reported endoscopic and symptomatic relief rates at the last point of follow-up. The effect of rabeprazole versus omeprazole was reported as relative risk (RR) of relief with a 95% confidence interval (CI).Results. The search identified 605 citations, and six RCTs containing 1,895 patients were eligible. Endoscopic relief rates were not significantly different between rabeprazole 20 mg and omeprazole 20 mg in treatment trials of up to 8 weeks. Heartburn relief rates were significantly different between the two groups for 8-week treatment trials. Adverse events were not significantly different between the two groups for 8-week treatment trials.Conclusion. These data suggest that rabeprazole demonstrates a clinical advantage over omeprazole in symptomatic relief but no significant difference in endoscopic relief of erosive GERD for up to 8 weeks of treatment. Rabeprazole and omeprazole were both tolerated by GERD patients.
Pharmacosomes: An Emerging Novel Vesicular Drug Delivery System for Poorly Soluble Synthetic and Herbal Drugs
Authors: Pandita Archana , Sharma Pooja
Published: September 2013

In the arena of solubility enhancement, several problems are encountered. A novel approach based on lipid drug delivery system has evolved, pharmacosomes. Pharmacosomes are colloidal, nanometric size micelles, vesicles or may be in the form of hexagonal assembly of colloidal drug dispersions attached covalently to the phospholipid. They act as befitting carrier for delivery of drugs quite precisely owing to their unique properties like small size, amphiphilicity, active drug loading, high entrapment efficiency, and stability. They help in controlled release of drug at the site of action as well as in reduction in cost of therapy, drug leakage and toxicity, increased bioavailability of poorly soluble drugs, and restorative effects. There has been advancement in the scope of this delivery system for a number of drugs used for inflammation, heart diseases, cancer, and protein delivery along with a large number of herbal drugs. Hence, pharmacosomes open new challenges and opportunities for improved novel vesicular drug delivery system.
A Preliminary Investigation of Ductility-Enhancement Mechanism through In Situ Nanofibrillation in Thermoplastic Matrix Composites
Authors: Patham Bhaskar , Thejaswini M. P. Poornendu
Published: September 2013

A preliminary investigation of interrelationships between tensile stress-strain characteristics and morphology evolution during deformation is conducted on a commercially available thermoplastic composite with a low-surface-energy nanofibrillating poly(tetrafluoroethylene) (PTFE) additive. In this class of composites, the deformation-associated nanofibrillation of the low-surface-energy additive has been hypothesized to provide an additional dissipation mechanism, thereby enhancing the ductility of the composite. This class of composites offers potential for automotive light weighting in exterior and interior body and fascia applications; it is therefore of interest to investigate processing-structure-property interrelationships in these materials. This study specifically probes the interrelationships between the plastic deformation within the matrix and the fibrillation of the low-surface-energy additive; tensile tests are carried out at two different temperatures which are chosen so as to facilitate and suppress plastic deformation within the matrix polymer. Based on these preliminary investigations, it is noted that PTFE fibrillation acts synergistically with the ductile deformation of the matrix resin resulting in higher strains to failure of the composite; the results also suggest that the mechanism of fibrillation-assisted enhancement of strains to failure may not operate in the absence of matrix plasticity.
Predicting Pyrolysis Products of PE, PP, and PET Using NRTL Activity Coefficient Model
Authors: FakhrHoseini Seyed Mousa , Dastanian Majid
Published: September 2013

Using thermodynamic models is a desired method for predicting an equilibrium when occurring in a system. If a thermodynamic model can predict an equilibrium condition in a pyrolysis, for a new way will be open for scientists in predicting equilibrium in a reaction without need to kinetic models. In this work, low‐density polyethylene, polypropylene, and polyethylene terephthalate were used instead of feed of pyrolysis process. The process was maintained at 500°C with 5 different temperature raising ratios 6, 8, 10, 12, and 14. Then the process was modeled thermodynamically using NRTL activity coefficient model. Using this model, the binary interaction coefficients were investigated for the system of “char, oil, and gas.” Results showed that polyethylene and polypropylene produced the maximum liquid product. Calculated RMSD objective function was 0.0157; that it is acceptable for this process.
Sudden Bilateral Sensorineural Hearing Loss Associated with HLA A1-B8-DR3 Haplotype
Authors: Psillas G. , Daniilidis M. , Gerofotis A. , Veros K. , Vasilaki A. , Vital I. , Markou K.
Published: September 2013

Sudden sensorineural hearing loss may be present as a symptom in systemic autoimmune diseases or may occur as a primary disorder without another organ involvement (autoimmune inner ear disease). The diagnosis of autoimmune inner ear disease is still predicated on clinical features, and to date specific diagnostic tests are not available. We report a case of bilateral sudden hearing loss, tinnitus, intense rotatory vertigo, and nausea in a female patient in which the clinical manifestations, in addition to raised levels of circulating immune complexes, antithyroglobulin antibodies, and the presence of the HLA A1-B8-DR3 haplotype, allowed us to hypothesize an autoimmune inner ear disease. Cyclosporine-A immunosuppressive treatment in addition to steroids helped in hearing recovery that occurred progressively with normalization of the hearing function after a five-month treatment. Cyclosporine-A could be proposed as a therapeutic option in case of autoimmune inner ear disease allowing the suspension of corticosteroids that, at high dose, expose patients to potentially serious adverse events.
The Distance toL∞in the Grand Orlicz Spaces
Authors: Farroni Fernando , Giova Raffaella
Published: September 2013

We establish a formula for the distance toL∞from the grand Orlicz spaceLΦ)Ωintroduced in Capone et al. (2008). A new formula for the distance toL∞from the grand Lebesgue spaceLn)Ωintroduced in Iwaniec and Sbordone (1992) is also provided.
Isolated Pulmonary Infective Endocarditis with Septic Pulmonary Embolism Complicating a Right Ventricular Outflow Tract Obstruction: Scarce and Devious Presentation
Authors: Abdelbar Abdelrahmen , Azzam Raed , Yap Kok Hooi , Abousteit Ahmed
Published: September 2013

We present a case of a fifty-three-year-old male who presented with severe sepsis. He had been treated as a pneumonia patient for five months before the admission. Investigations revealed isolated pulmonary valve endocarditis and septic pulmonary embolism in addition to undiagnosed right ventricular outflow tract (RVOT) obstruction. The patient underwent surgery for the relief of RVOT obstruction by substantial muscle resection of the RVOT, pulmonary artery embolectomy, pulmonary valve replacement, and reconstruction of RVOT and main pulmonary artery with two separate bovine pericardial patches. He was discharged from our hospital after 6 weeks of intravenous antibiotics. He recovered well on follow-up 16 weeks after discharge. A high-suspicion index is needed to diagnose right-side heart endocarditis. Blood cultures and transesophageal echocardiogram are the key diagnostic tools.
Amperometric Detection ofBacillus anthracisSpores: A Portable, Low-Cost Approach to the ELISA
Authors: Peckham Gabriel D. , Hew Brian E. , Waller David F. , Holdaway Charlie , Jen Michael
Published: September 2013

Antibody-based detection assays are generally robust, a desirable characteristic for in-the-field use. However, to quantify the colorimetric or fluorescent signal, these assays require expensive and fragile instruments which are ill-suited to in-the-field use. Lateral flow devices (LFDs) circumvent these barriers to portability but suffer from poor sensitivity and subjective interpretation. Here, an antibody-based method for detectingBacillus anthracisspores via amperometric signal generation is compared to ELISA and LFDs. This amperometric immunoassay uses antibody conjugated to magnetic beads and glucose oxidase (GOX) along with the electron mediator 2, 6-dichlorophenolindophenol (DCPIP) for production of a measurable current from a 0.4 V bias voltage. With similar sensitivity to ELISA, the assay can be completed in about 75 minutes while being completely powered and operated from a laptop computer. Immunoassay amperometry holds promise for bringing low-cost, quantitative detection of hazardous agents to the field.
Constraint Study for a Hand Exoskeleton: Human Hand Kinematics and Dynamics
Authors: Chen Chen Fai , Appendino Silvia , Battezzato Alessandro , Favetto Alain , Mousavi Mehdi , Pescarmona Francesco
Published: September 2013

In the last few years, the number of projects studying the human hand from the robotic point of view has increased rapidly, due to the growing interest in academic and industrial applications. Nevertheless, the complexity of the human hand given its large number of degrees of freedom (DoF) within a significantly reduced space requires an exhaustive analysis, before proposing any applications. The aim of this paper is to provide a complete summary of the kinematic and dynamic characteristics of the human hand as a preliminary step towards the development of hand devices such as prosthetic/robotic hands and exoskeletons imitating the human hand shape and functionality. A collection of data and constraints relevant to hand movements is presented, and the direct and inverse kinematics are solved for all the fingers as well as the dynamics; anthropometric data and dynamics equations allow performing simulations to understand the behavior of the finger.
New Quasi-Coincidence Point Polynomial Problems
Authors: Chen Yi-Chou , Lai Hang-Chin
Published: September 2013

LetF:ℝ×ℝ→ℝbe a real-valued polynomial function of the formF(x,y)=as(x)ys+as-1(x)ys-1+⋯+a0(x), where the degreesofyinF(x,y)is greater than or equal to1. For arbitrary polynomial functionf(x)∈ℝ[x],x∈ℝ, we will find a polynomial solutiony(x)∈ℝ[x]to satisfy the following equation: (*):F(x,y(x))=af(x), wherea∈ℝis a constant depending on the solutiony(x), namely, a quasi-coincidence (point) solution of (*), andais called a quasi-coincidence value. In this paper, we prove that (i) the leading coefficientas(x)must be a factor off(x), and (ii) each solution of (*) is of the formy(x)=-as-1(x)/sas(x)+λp(x), whereλis arbitrary andp(x)=c(f(x)/as(x))1/sis also a factor off(x), for some constantc∈ℝ, provided the equation(*)has infinitely many quasi-coincidence (point) solutions.
SCIRR39 Promotes Neurite Extension via RhoA in NGF-Induced PC12 Cells
Authors: Zhao C.F. , Liu Y. , Ni Y.L. , Yang J.W. , Hui H.D. , Sun Z.B. , Liu S.J.
Published: September 2013

SCIRR39 is an identified upregulated gene in rat primary neuron injury and/or regeneration process with roles largely unexplored. Using real-time quantitative PCR, Western blotting and immunofluorescence, SCIRR39 expression was detected in normal PC12 cells and upregulated in differentiated cells. The results of cell proliferation by Cell Counting Kit and cell cycle by flow cytometry indicated that SCIRR39 inhibited cell proliferation and induced the decrease in S phase. Importantly, immunofluorescent and RhoA pull-down assays showed that SCIRR39 strongly affected the neurite extension of NGF-treated PC12 cells through a RhoA-dependent mechanism, but the truncated mutants of SCIRR39 containing a truncation from 141AA to 211AA or from 397AA to 424AA failed to mock the SCIRR39 effect on neurite extension. Moreover, change of SCIRR39 expression in NGF-treated PC12 cells regulated the expression and phosphorylation of Fyn, a regulator of RhoA activity, but not the expression of ROCK II protein. Finally, immunofluorescence and RhoA pull-down assays revealed that obvious inhibition of neurite extension by SCIRR39 shRNA was reversed by RhoA inhibitor C3-transferase. Our results indicated that SCIRR39 increased the neurite extension in NGF-treated PC12 cells via RhoA, suggesting that SCIRR39 contributes to the regeneration of neuron injury by specifically altering the differentiation program.
Orchidectomy after Primary Chemotherapy for Metastatic Testicular Cancer
Authors: Ramsey S. , Kerr G. , Howard G.C.W. , Donat R.
Published: September 2013

Objective: To examine the outcome of orchidectomy following primary chemotherapy in patients with metastatic testicular cancer. Patients and Methods: This was a retrospective analysis of patients who underwent primary chemotherapy without initial orchidectomy for testicular cancer between 1982 and 2006. The patients were identified from the regional oncology cancer database in our tertiary referral hospital. Their case notes were reviewed regarding initial presentation, chemotherapy, clinical progress and pathological outcomes following surgery. Results: 21 evaluable patients were identified (14 non-seminomatous germ cell tumours, 7 seminomas). 16 patients underwent standard orchidectomy within 12 months of commencing chemotherapy and 5 patients underwent significantly delayed orchidectomy (19-68 months, mean 45.1 months). Orchidectomy in the standard group showed tumour necrosis or a scar in 13 patients (81%) and differentiated or mature teratoma in 3 patients associated with bulky poorly responsive retroperitoneal disease (19%). In the delayed orchidectomy group 3 out of 5 patients had viable seminoma, of which two were associated with carcinoma in situ. Conclusion: Our study raises concerns as regards a potentially high risk of late tumour development in testes which are preserved following apparent tumour resolution after chemotherapy.
Phosphohistone H3 and Ki-67 Labeling Indices in Cytologic Specimens from Well-Differentiated Neuroendocrine Tumors of the Gastrointestinal Tract and Pancreas: A Comparative Analysis Using Automated Image Cytometry
Authors: Fung Adele D. , Cohen Cynthia , Kavuri Sravankumar , Lawson Diane , Gao Xin , Reid Michelle D.
Published: September 2013

Background: Ki-67 proliferation index was recently incorporated in the grading of neuroendocrine neoplasms (NENs) of the gastrointestinal tract (GIT) and pancreas. These are now divided into well-differentiated neuroendocrine tumors (WDNETs, grades 1 and 2) and poorly differentiated neuroendocrine carcinomas (grade 3). While Ki-67 is an established proliferation marker in NENs, phosphohistone H3 (PHH3), a newer marker of mitotic activity, is not. Methods: We determined Ki-67 and PHH3 indices on cytologic samples from WDNETs of the GIT and pancreas using an automated cellular imaging system (ACIS®). Results: There was a strong correlation between Ki-67 and PHH3 indices generated by ACIS on cytologic samples. However, in some cases the two stains caused conflicting grades within the same tumor. Conclusion: Both antibodies stain cells in different phases of the cell cycle which may cause discordant grades, thus affecting patient management and prognostication. Ki-67 staining is stronger than PHH3, making ‘hot spots' easier to identify on ACIS. Ki-67 is more ideal than PHH3 for staining NENs, especially in tumors with borderline grades. Because PHH3 generates lower mitotic indices it should not be used as a proliferation marker in NENs until its expression has been further characterized.
Application of the Bethesda System for Reporting Thyroid Cytopathology in the Eastern Province of Saudi Arabia: Phase I Pilot Retrospective Analysis
Authors: Al-Abbadi Mousa A. , Shareef Sameera Q. , Ali Jassim A. , Yousef Mohammad M.
Published: September 2013

We analyzed and evaluated our adequacy rate and the classification of our thyroid aspirates using the Bethesda System for Reporting Thyroid Cytopathology (BSRTC). All thyroid fine needle aspirates that were collected or referred to our institution were reviewed and reclassified according to the BSRTC. The results were tabulated and analyzed. Those with histological resection were correlated with our revised cytopathological evaluation using the BSRTC. A total of 205 thyroid aspirates from 186 patients were reviewed. There were 149 females (80%) and 37 males (20%) ranging in age from 23 to 81 (average age 48) years. All slides were reclassified using the BSRTC. The previous interpretations were not consistent with any apparent standards. The nondiagnostic rate was found to be 22%. Five cases were considered false negative and were upgraded to a more serious category with higher risk of malignancy. The high unsatisfactory rates can be reduced by an adequacy interpretation at the time of the procedure. The risk of malignancy in our cohort increased with each increase in the BSRTC category (I-VI). Communication about and awareness of the BSRTC and its implications by all our clinicians is a prime target of this study and is still work in progress. Hopefully, this study will increase the awareness of the BSRTC and its intended benefits in our region.
Discriminant Analysis between Malignant Mesothelioma and Reactive Mesothelium Using Nuclear Three-Dimensional Analysis Is Useful for Morphologically Suspicious Cases
Authors: Washiya Kiyotada , Mizuki Yuuta , Nakamura Minori , Kakinuma Hirokuni , Saegusa Makoto , Satoh Yukitoshi , Yoshioka Haruhiko , Watanabe Jun
Published: September 2013

Objective: Morphological discrimination between malignant mesothelioma (MM) and reactive mesothelium (RM) is often difficult. Stereological analysis of nuclear luminance using centrifuged smear samples from coelomic fluid and discriminant analysis based on Mahalanobis distance may help to more accurately discriminate between MM and RM. In the present study, discriminant analysis was conducted on cytological specimens using the auto-smear method in a blinded manner with regard to histological results. Study Design: Coelomic fluid samples of 28 cases, cytologically diagnosed using the auto-smear method, were analyzed to determine pixel counts, the number of focus layers, 3-dimensional variation in the coefficient of variation of nuclear luminance between the focus layers as well as roundness in about 30-50 atypical cell nuclei per case. These measurements were employed to determine malignancy based on Mahalanobis distance. Results: Discrimination rates were as high as 91.7% for MM and 82.7% for RM. The discrimination rates of MM with histology were >80% in 8 of 10 suspicious cases with the initial cytology. Conclusion: Our method allowed accurate discrimination between MM and RM and provides a useful alternative for the diagnosis of suspicious cases where morphological diagnosis of malignancy is difficult.
The True Nature of Atypical Breast Cytology
Authors: Weigner J. , Zardawi I. , Braye S.
Published: September 2013

Background: Atypical breast cytology is a poorly understood heterogeneous category with limited clinical utility but significant implications for patient management. Objective: To provide an insight into the true nature of atypical breast cytology in screening-detected (asymptomatic) and symptomatic settings, and find strategies for reducing the use of this diagnostic category. Materials and Methods: A total of 6,415 breast cytology samples were processed between January 2004 and December 2008. An atypical cytological diagnosis was rendered in 256 (4%) of the cases. A blind microscopic review of the atypical cases was conducted and results were correlated with subsequent histological and/or clinical outcomes. Results: Follow-up information by histology was available in 85.5%, by repeat fine-needle aspiration (FNA) in 3.5% and by imaging or clinical follow-up in 10.2% of the cases. Two patients (0.8%) were lost to follow-up. Of the 254 cases with follow-up, 62.6% were benign and 37.4% were malignant. The benign to malignant ratios were 1:1 and 2:1 in the screening and symptomatic groups, respectively. The atypical category in the screening population mostly yielded fat necrosis, complex sclerosing lesions and low- to intermediate-grade carcinoma on follow-up. The main outcomes in the symptomatic group were papilloma, fibroadenoma, ductal carcinoma in situ and lobular carcinoma. Preanalytical (suboptimal samples) factors were encountered in 34.8% and interpretative factors in 65.2% of the cases. Uncertainty about cellular morphology was attributed to such a diagnosis in 38 (14.8%) of the cases, architectural complexity in 137 (53.5%) and morphology and architecture in 70 (27.3%); 4.3% of cases were considered nondiagnostic. Conclusion: The atypical category is a necessary diagnosis but of limited use from a patient management perspective. Some preanalytical factors such as poor sample quality can be minimized by the involvement of cytopathologists in the FNA procedure. The use of the atypical category is partly dependent on the experience and confidence of the reporting pathologist. Assigning a case to this category is also likely to be unduly influenced by clinical or radiological findings. Our study indicates that the use of the atypical category can be reduced by up to 40% by appreciating these contributing factors. The practical utilization of the atypical category in breast cytology remains subjective and further study is required to identify useful objective criteria.
Mechanisms of Tissue Remodeling in Inflammatory Bowel Disease
Authors: Rieder Florian , Fiocchi Claudio
Published: September 2013

The clinical course of inflammatory bowel disease (IBD) is highly heterogeneous and often unpredictable, with multiple and serious complications that range from stricture formation to bowel obstruction or perforation, fistula formation and the need for surgery. All these problems are manifestations of tissue remodeling, a secondary but universal response to the insults of chronic inflammation. The factors involved in tissue remodeling are several, including the site and duration of inflammation, soluble molecules, the gut microbiota, and the type of mesenchymal cell response. The prototypical and most common type of tissue remodeling in IBD, and Crohn's disease (CD) in particular, is a fibrotic response, and this review will focus on the factors and mechanisms involved in fibrogenesis, and speculate on what is needed for the development of a rational treatment of intestinal fibrosis.
Endoscopic Assessment of the Small Bowel
Authors: Eliakim Rami , Carter Dan
Published: September 2013

Background: Small bowel imaging and endoscopy in IBD have undergone a tremendous change and advancement in the recent years. Modalities shifted from gastroscopy, colonoscopy and small bowel follow through to ileocolonoscopy, CT or MR enteroscopy, wireless video capsule endoscopy and balloon-assisted enteroscopy. Methods: We reviewed the present role of endoscopy in assessing the small bowel in the context of IBD. Results: Endoscopy has a major role in the diagnosis of IBD, in the assessment of its extent, treatment of complications, assessment of the success of various medications and as a predictor of disease course. Wireless capsule endoscopy (WCE) is a relatively new tool allowing direct, patient-friendly visualization of the entire small bowel mucosa. It has gained a substantial role in the evaluation of patients with suspected Crohn's disease (CD) and indeterminate colitis. WCE has a high positive predictive value in patients with suspected CD, when one uses more than two of the International Conference on Capsule Endoscopy criteria, and not less important a very high negative predictive value in patients with suspected CD. Its role in patients with known CD, in the assessment of their disease activity and extent, assessment of postsurgical small bowel recurrence and evaluation of mucosal healing is still unclear. Balloon-assisted enteroscopy has established its role as a complementary tool in cases where there is a need for biopsy or treatment (dilatation of strictures). Conclusions: The present review summarizes the role of endoscopy in the assessment of the small bowel in the context of IBD.
Challenging Question: Can We Diagnose Crohn's Disease without Histology?
Authors: Griffiths Anne M.
Published: September 2013

No single test is diagnostic of Crohn's disease (CD). In the presence of a compatible clinical presentation, diagnosis is by convention confirmed by a combination of imaging, serologic, endoscopic and histologic investigations. This diagnostic recommendation should be maintained, even though histology is often ‘compatible with' rather than ‘diagnostic of' suspected CD. The importance of histology varies depending on the specific sites of macroscopic disease. Histology is particularly important in distinguishing type of inflammatory bowel disease, when the colon predominantly is involved, and in confirming CD when macroscopic disease is atypically located.