bluuebunny/crossref_metadata_2025 huggingface dataset:
The dominant wave mode within a trailing line vortex
Authors: Denier James P. , Stott Jillian A. K.
Published: November 2004

We identify the dominant, or most unstable, wave mode for the flow in a trailing line vortex. This dominant mode is found to reside in a wavenumber regime between that of inviscid wave modes and the viscous upper branch neutral wave modes. A reevaluation of the growth rate in the vicinity of the upper branch of the curve of neutral stability allows us to predict the neutral value of the azimuthal and axial wavenumber as a function of the imposed swirl within the trailing line vortex.
Modeling and analysis of high-speed electro-optic modulation in high confinement silicon waveguides using metal-oxide-semiconductor configuration
Authors: Barrios C. A. , Lipson M.
Published: November 2004

We analyze the electrical and optical properties of a silicon electro-optic waveguide modulator using a metal-oxide-semiconductor (MOS) configuration. The device performance is studied under different modes of operation of the MOS diode and gate oxide thicknesses. Our calculations indicate that this scheme can be used for achieving high-speed submicron waveguide active devices on silicon on insulator. A microring resonator intensity modulator is predicted to exhibit switching times on the order of tens of picoseconds with modulation depth of 73% by employing a bias voltage of only 5 V.
Multicarrier analysis of semiconducting films by including the effect of magnetoresistance: Application in β-FeSi2 films
Authors: Tassis D. H. , Evangelinos D. , Valassiades O. , Dimitriadis C. A.
Published: November 2004

A method of multicarrier analysis of semiconducting β-FeSi2 thin films is described, based on Hall and magnetoresistance data from variable magnetic field measurements. We exploit both the longitudinal and transverse resistivity components to extract the concentration and mobility of each carrier. Nonlinear fitting is used to fit simultaneously the magnetoresistivity and Hall resistivity data versus the magnetic field. The criteria and the procedure, as well as the selection of a proper function for minimization are discussed. Application of the proposed method in β-FeSi2 thin films revealed the presence of multiple carriers, explaining the nonlinear dependence of the Hall voltage on the magnetic field. Analysis of the Hall data at various temperatures revealed the most probable scattering mechanisms and a thermally activated behavior of the carrier concentration.
Fluid modeling of electron heating in low-pressure, high-frequency capacitively coupled plasma discharges
Authors: Chen Guangye , Raja Laxminarayan L.
Published: November 2004

Fluid modeling approaches encounter several shortcomings when used for simulation of capacitively coupled plasma discharges, especially under low-pressure and high-frequency conditions. For example, fluid models fail to accurately predict important features such as the collisionless electron heating and the electron temperature profiles in these discharges. We improve the classical fluid modeling approach to include the full electron momentum equation instead of the approximate drift-diffusion and a nonlocal collisionless electron heat flux terms instead of the Fourier heat flux form. A one-dimensional form of the fluid model is used in our studies. Improved predictions of the collisionless electron heating effect, charged species densities, and sheath electron temperature profiles are shown. Also accurate prediction of discharge impedance characteristics in the low-pressure, high-frequency regime are demonstrated.
Field sweep rate dependence of domain-wall speed distributions in a thin Ni80Fe20 film
Authors: Moore T. A. , Ionescu A. , Bland J. A. C.
Published: November 2004

The magnetization reversal in a thin (100nm) Ni80Fe20∕GaAs(001) film prepared by molecular-beam epitaxy has been investigated using a focused spot Kerr magnetometer. The field was sinusoidal and applied along an in-plane easy axis, with sweep rate at the coercive point in the range ∼1kOe∕s–1MOe∕s. Real time measurements of the Kerr response enabled a study of the probability distributions P(V) of the domain-wall speed as a function of sweep rate. The shape of P(V) changes from being characteristic of stochastic domain-wall motion at low sweep rate to being characteristic of quasicontinuous domain-wall motion at high sweep rate. Increasing the diameter of the focused spot from 2to80μm increases the number of domain walls participating in the reversal within the probed area, which leads to an averaging effect and dulls the transition from stochastic to quasicontinuous wall motion seen in the probability distributions.
Generation and measurements of high energy injection electrons from the high density laser ionization and ponderomotive acceleration
Authors: Ting A. , Kaganovich D. , Gordon D. F. , Hubbard R. F. , Sprangle P.
Published: November 2004

The high density regime of the laser ionization and ponderomotive acceleration (HD-LIPA) injector provides high injection bunch charge by employing a high density gas jet. Measurements and simulations confirmed that space charge effects lead to a distribution of high energy LIPA electrons in the directly forward directions in violation of the LIPA angle-energy relationship. These electrons also have much higher energies than predicted, indicating that further acceleration by mechanisms such as the self-modulated laser wakefield acceleration may be present in the HD-LIPA environment.
Transient response of Reynolds stress transport to spanwise wall oscillation in a turbulent channel flow
Authors: Xu Chun-Xiao , Huang Wei-Xi
Published: November 2004

Turbulent channel flow at low Reynolds number subjected to spanwise wall oscillation is studied by direct numerical simulation. The Reynolds stress budgets under the influence of the oscillating wall are analyzed in the first two oscillation periods. It is found that the spanwise velocity fluctuations are enhanced at the very beginning of the wall oscillation, and the subsequent global turbulence suppression is caused by the sustained attenuation of the pressure-strain terms. The hindrance of intercomponent transfer of turbulent kinetic energy by the oscillating wall is a mechanism of the skin-friction reduction.
Vortex synchronization regions in shedding from an oscillating cylinder
Authors: Ponta Fernando L. , Aref Hassan
Published: November 2004

A classification of the vortex patterns in the wake of a normally oscillating cylinder was given by Williamson and Roshko who also studied when the various vortex patterns would occur. Using a symbolic code of letters and numbers that describes the combination of pairs and single vortices shed during each cycle of the forced oscillation of the cylinder, they gave a “map” of vortex-synchronization regions with the wavelength and amplitude of the oscillation as coordinates. In this study, we provide a theoretical basis for the experimental Williamson–Roshko map of vortex synchronization. We show that the region boundaries consist of two families of curves given by specific relations between the values of two nondimensional parameters defining the map. We construct a synthetic map that compares favorably with the experimental data.
Reducing the immigration of suspected leafhopper vectors and severity of Australian lucerne yellows disease
Authors: Pilkington L. J. , Gurr G. M. , Fletcher M. J. , Elliott E. , Nikandrow A. , Nicol H. I.
Published: November 2004

Three newly-sown lucerne stands in the mid Lachlan Valley region of New South Wales, Australia, were sampled, over 50 weeks, for Australian lucerne yellows disease symptom distribution and severity. Leafhopper populations were also monitored. Symptoms developed in all 3 stands within 32 weeks of sowing. There were statistically significant spatial differences in the density of symptomatic plants for 2 dates at this and another site. Two possible insect vectors, Austroagallia torrida and Batracomorphus angustatus were more numerous in some sections of crop margins at 2 sites. These 2 species and a third possible insect vector Orosius argentatus each had a statistically significant spatial and temporal correlation with symptomatic plant numbers for at least 1 site date. Two subsequent border treatment experiments evaluated the effect of crop-margin treatments on leafhopper movement into and from the stand. The second border treatment experiment examined also the treatment effect on Australian lucerne yellows disease symptomatic plant numbers. Treatment with insecticide or herbicide significantly reduced the overall movement of leafhoppers. In addition, the insecticide treatment lowered the incidence of disease expression in adjacent lucerne. Results suggest that there is scope for management of this plant disease by reducing immigration of leafhopper vectors into lucerne from non-crop vegetation.
Application of remote sensing and GIS to locate priority intervention areas after wildland fires in Mediterranean systems: a case study from south-eastern Spain
Authors: Ruiz-Gallardo J. Reyes , Castaño Santiago , Calera Alfonso
Published: November 2004

Wildland fires are one of the major causes of ecosystem degradation, especially in semiarid climates, where the erosion hazard is high. The identification of potential erosion zones is typically difficult as it requires expensive field and laboratory work. This paper proposes a methodology based on remote sensing and GIS techniques, which permits speedy identification of erosional areas in a semi-automatic way, tested in a large burn scar in south-eastern Spain. Inputs were slope, aspect, and fire severity. In order to obtain the latter a new method has been proposed, based on the difference in NDVI between two images (acquired before and after the fire event). Combining these maps in a GIS, a Forest Intervention Priority map (FIP) is produced, which identifies areas of high erosion potential. Field work was conducted to assess the method. Results indicate that the applied methodology reliably predicted the extent of very severe fire and, further, was generally useful for identifying sites of significant erosion. Additional work is required to refine: (1) remotely sensed fire severity thresholds, particularly for other Mediterranean forest systems and substrate conditions; and (2) associated mapping tools for informing post-fire management applications.
Investigating the Haines Index using parcel model theory
Authors: Jenkins Mary Ann
Published: November 2004

By using parcel model theory to construct a two-dimensional parameter space formed by low-level atmospheric stability and moisture, a simple framework on which to examine certain fire parcel properties associated with vertical column development is established. This framework is used to investigate if the Haines Index has some skill at predicting wildfire severity, where wildfire severity is assumed to be directly connected to vertical column development and the result of significant fire parcel ascent. By modeling the ascent of a moist, entraining fire parcel in four different background states—a 3 km deep boundary layer, a 2 km deep boundary layer, a 3 km deep boundary layer topped by an inversion layer, and a 2 km deep boundary layer topped by an inversion layer—the study shows that parcel properties that describe ascent and vertical column development are most significant when the boundary layer temperature lapse rate is near adiabatic and lower-level atmospheric humidity is relatively high. A shallower instead of a deeper boundary layer lowers parcel ascent, and an upper-level inversion lowers parcel ascent even further. This study shows that entraining fire parcel properties and magnitudes associated with significant ascent do not necessarily correspond to a Haines Index for a potential for high fire severity. The results suggest that the Haines Index may need to be refined or reformed depending on the stability and humidity in the boundary layer and vertical structure of the atmosphere. This study is a start to understanding the influence of the background state on fire parcel convection and an attempt to explain how the Haines Index works from an elementary but physical point of view.
A comparison of thermocouples and temperature paints to monitor spatial and temporal characteristics of landscape-scale prescribed fires
Authors: Iverson Louis R. , Yaussy Daniel A. , Rebbeck Joanne , Hutchinson Todd F. , Long Robert P. , Prasad Anantha M.
Published: November 2004

A method to better monitor landscape-level fire characteristics is presented. Three study areas in southern Ohio oak-hickory (Quercus-Carya) forests were established with four treatment areas of ~20 ha each: control (C), burn only (B), thin only (T) or thin plus burn (TB). Two independent measures useful for qualitatively characterising fire intensity were established on a 50-m grid, resulting in over 120 sampling locations at each site, in the burned areas: aluminum tags painted with temperature-sensitive paints, and logger-probe units that logged probe temperature every 2 s during burns. Fires were conducted in spring 2001. The logger-probe units allowed five measures qualitatively related to fire intensity or timing to be calculated at each grid point: maximum probe temperature; duration of probe temperature above 30°C; a heat index, defined as the summed temperatures above 30°C; time of maximum temperature; and estimated rate of spread. Maximum temperatures recorded by the two measuring systems were highly correlated (r2 = 0.83). Relative to painted tags, logger-probe units provide information useful for assessing some other components of fire behaviour. The temporal recording of temperatures allowed us to prepare a web-based simulation of the fires. Heat index and rate of spread estimates provided additional fire information. The TB units consistently burned cooler than the B units, perhaps because of uncured slash and a disrupted fuel bed in those units.
Does firefighting foam affect the growth of some Australian native plants?
Authors: Hartskeerl Kerry , Simmons Dianne , Adams Robyn
Published: November 2004

Firefighting foams (Class A foams) are an effective and widespread firefighting tool, and are frequently used in environmentally sensitive areas. They are known to be ecologically damaging in aquatic environments; however, their impacts at the plant species or ecosystem level are relatively unknown. Reports of shoot damage to plants, suppressed flowering and changes in plant community composition suggest that the environmental damage caused by their use may be unacceptable. Applications of four levels of foam to seedlings of seven Australian plant species, from five representative and widespread families, showed no detectable impacts on a range of vegetative growth characteristics. The results are encouraging for continued use of firefighting foam in sensitive natural habitats.
Inhibition of Leukocyte Adherence Enables Venular Control of Capillary Perfusion in Streptozotocin‐Induced Diabetic Rats
Authors: NELLORE KAVITHA , HARRIS NORMAN R.
Published: November 2004

Objective: Vasoactive molecules can diffuse from venules to dilate closely paired arterioles and enhance capillary perfusion. Venular control of capillary flow has been found to be dependent on nitric oxide (NO), which might be scavenged rapidly in diabetic microvasculature due to the presence of activated leukocytes. This study attempts to improve venular control of capillary flow using fucoidan, which inhibits venular leukocyte adhesion.

Methods: Microvascular red blood cell velocity was measured in the mesentery of streptozotocin‐induced diabetic rats, with and without fucoidan treatment, and in normal rats. Arteriolar pathways leading to branching capillaries were videotaped to measure the percent of the surrounding area occupied by a venule (% pairing). Microvascular wall NO was measured using fluorescent diaminofluorescein‐2‐diacetate in diabetic rats, with and without fucoidan treatment.

Results: In normal rats, close pairing of venules to arterioles resulted in faster capillary flow. However, after 4–5 weeks of diabetes, the correlation between capillary velocity and % pairing was no longer significant. Capillary velocity and % pairing decreased ∼ 50% in comparison to normal rats. Treatment of diabetic rats with fucoidan restored venular control of capillary flow and increased NO levels.

Conclusion: Leukocyte‐derived mediators that scavenge NO may lead to inadequate venular control of capillary flow in diabetes.
Arteriolar Responses to Vasodilator Stimuli and Elevated PO2 in Renin Congenic and Dahl Salt‐Sensitive Rats
Authors: DRENJANCEVIC‐PERIC INES , GREENE ANDREW S. , KUNERT MARY PAT , LOMBARD JULIAN H.
Published: November 2004

Objectives: Angiotensin II suppression leads to impaired vascular relaxation in normotensive animals on a high‐salt diet. The goal of this study was to determine whether normal vascular reactivity could be restored by transferring the chromosomal region carrying the Dahl salt‐resistant (R) renin gene into the Dahl salt‐sensitive (SS) genetic background in a strain of renin congenic rats (RGRR).

Methods: Male RGRR and SS rats were fed low‐salt (0.4%) and high‐salt (4%) diets for 4 weeks. The responses of cremaster muscle arterioles to acetylcholine (ACh), sodium nitroprusside (SNP), and elevated PO2 were assessed using video microscopy.

Results: ACh‐induced dilation was significantly enhanced in RGRR on a high‐salt diet compared to SS rats, while dilation to the NO donor SNP was similar in both strains. A high‐salt diet significantly enhanced arteriolar constriction in response to elevated PO2, in both SS and RGRR rats.

Conclusions: These data suggest that transfer of the chromosomal region containing the renin gene is crucial in the recovery of ACh‐induced dilation of arterioles in RGRR rats vs. SS rats, and that factors in the SS genetic background contribute to an enhanced sensitivity to elevated PO2, independent of genes on chromosome 13.
Pentastarch in a Balanced Solution Reduces Hepatic Leukocyte Recruitment in Early Sepsis
Authors: ONDIVEERAN HARI KUMAR , FOX‐ROBICHAUD ALISON E.
Published: November 2004

Objective: To characterize the hepatic leukocyte endothelial cell interactions occurring in early sepsis and to determine whether this is influenced by fluid treatment.

Methods: Sepsis was induced by cecal ligation and perforation in C57Bl/6 mice. One of 6 iv fluid regimes was given immediately postsurgery and at 6 h. The hepatic microcirculation was examined by intravital microscopy at 6 h.

Results: All 0.9% saline‐based solutions were associated with an increase in leukocyte–endothelial cell interactions as demonstrated by an increase in the rolling flux in the sham and naïve mice. In the septic mice treated with normal saline, there was a 20‐fold increase in leukocyte adhesion within the postsinusoidal venules, compared to sham mice. Treatment with lactated Ringer's reduced the sepsis‐mediated leukocyte recruitment by 50%. When septic mice received 6% pentastarch in a balanced solution or 3% saline, venular leukocyte adhesion was reduced by an additional 50%. When the pentastarch was prepared in normal saline there was no further reduction in venular leukocyte adhesion compared to the lactated Ringer's‐treated mice. All hyperosmolar solutions improved the sepsis‐induced reduction in sinusoidal perfusion but only the pentastarch in the balance solution significantly reduced the number of adherent leukocytes within the sinusoids.

Conclusions: Hepatic leukocyte recruitment occurs early in sepsis. Pentastarch in a balanced solution but not in normal saline significantly reduces hepatic leukocyte recruitment, suggesting solution composition, as well as osmolarity impact the innate immune response.
Antecedent Ethanol Ingestion Prevents Postischemic P‐Selectin Expression in Murine Small Intestine
Authors: DAYTON CATHERINE , YAMAGUCHI TAIJI , KAMADA KAZUHIRO , CARTER PATSY , KORTHUIS RONALD J.
Published: November 2004

Objective: Ethanol ingestion 24 h prior to ischemia and reperfusion (I/R) prevents postischemic leukocyte rolling and adhesion in postcapillary venules of the small bowel. Since I/R‐induced leukocyte rolling is critically dependent on the expression of P‐selectin by endothelial cells lining postcapillary venules, the authors hypothesized that antecedent ethanol consumption would attenuate postischemic expression of this adhesive ligand.

Methods: To address this postulate, P‐selectin expression was evaluated using a dual radiolabeled monoclonal antibody technique in the jejunum of mice that received either distilled water vehicle or ethanol by gavage (dose) on day 1 and then were subjected to sham I/R (nonischemic controls) or I/R (20 min ischemia/60 min reperfusion) 24 h later.

Results: I/R was associated with a 2‐fold increase in P‐selectin expression relative to nonischemic controls, an effect that was largely abolished by antecedent ethanol ingestion. Exposing the bowel to adenosine deaminase or adenosine A2 receptor antagonists (DMPX or ZM241385), an NO synthase inhibitor (L‐NIO) or an NO scavenger (PTIO), or an antioxidant (mercaptoproprionyl glycine) during the period of ethanol exposure on day 1 prevented the beneficial effect of ethanol to limit I/R‐induced P‐selectin expression, on day 2.

Conclusions: The data indicate that antecedent ethanol exposure prevents postischemic P‐selectin expression on day 2 by a mechanism that is triggered by adenosine A2 receptor activation and the formation of nitric oxide (NO) and reactive oxygen species (ROS) during the period of ethanol exposure on day 1.
Integrin αv-mediated inactivation of p53 controls a MEK1-dependent melanoma cell survival pathway in three-dimensional collagen
Authors: Bao Wenjie , Strömblad Staffan
Published: November 2004

Integrin αv is required for melanoma cell survival and tumor growth in various models. To elucidate integrin αv-mediated melanoma cell survival mechanisms, we used a three-dimensional (3D) collagen gel model mimicking the pathophysiological microenvironment of malignant melanoma in the dermis. We found that integrin αv inactivated p53 and that suppression of p53 activity by dominant negative p53 or p53-small interfering RNA obviated the need for integrin αv for melanoma cell survival in 3D-collagen and for tumor growth in vivo. This indicates that integrin αv-mediated inactivation of p53 functionally controls melanoma cell survival. Furthermore, we found that melanoma cell integrin αv was required for MAPK kinase (MEK) 1 and extracellular signal-regulated kinase (ERK)1/2 activity in 3D-collagen, whereas inhibition of MEK1 activity induced apoptosis. Surprisingly, MEK1 and ERK1/2 activities were restored in integrin αv-negative melanoma cells by suppression of p53, whereas concomitant block of MEK1 induced apoptosis. This suggests that integrin αv controls melanoma cell survival in 3D-collagen through a pathway involving p53 regulation of MEK1 signaling.
Mlp-dependent anchorage and stabilization of a desumoylating enzyme is required to prevent clonal lethality
Authors: Zhao Xiaolan , Wu Chia-Yung , Blobel Günter
Published: November 2004

Myosin-like proteins 1 and 2 (Mlp1 and Mlp2) form filaments attached to the nucleoplasmic side of the nuclear pore complexes via interaction with the nucleoporin Nup60. Here, we show that Mlps and Nup60, but not several other nucleoporins, are required to localize and stabilize a desumoylating enzyme Ulp1. Moreover, like Mlps, Ulp1 exhibits a unique asymmetric distribution on the nuclear envelope. Consistent with a role in regulating Ulp1, removal of either or both MLPs affects the SUMO conjugate pattern. We also show that deleting MLPs or the localization domains of Ulp1 results in DNA damage sensitivity and clonal lethality, the latter of which is caused by increased levels of 2-micron circle DNA. Epistatic and dosage suppression analyses further demonstrate that Mlps function upstream of Ulp1 in 2-micron circle maintenance and the damage response. Together, our results reveal that Mlps play important roles in regulating Ulp1 and subsequently affect sumoylation stasis, growth, and DNA repair.
Protein oligomerization modulates raft partitioning and apical sorting of GPI-anchored proteins
Authors: Paladino Simona , Sarnataro Daniela , Pillich Rudolf , Tivodar Simona , Nitsch Lucio , Zurzolo Chiara
Published: November 2004

An essential but insufficient step for apical sorting of glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs) in epithelial cells is their association with detergent-resistant microdomains (DRMs) or rafts. In this paper, we show that in MDCK cells both apical and basolateral GPI-APs associate with DRMs during their biosynthesis. However, only apical and not basolateral GPI-APs are able to oligomerize into high molecular weight complexes. Protein oligomerization begins in the medial Golgi, concomitantly with DRM association, and is dependent on protein–protein interactions. Impairment of oligomerization leads to protein missorting. We propose that oligomerization stabilizes GPI-APs into rafts and that this additional step is required for apical sorting of GPI-APs. Two alternative apical sorting models are presented.
The FG-repeat asymmetry of the nuclear pore complex is dispensable for bulk nucleocytoplasmic transport in vivo
Authors: Zeitler Bryan , Weis Karsten
Published: November 2004

Nucleocytoplasmic transport occurs through gigantic proteinaceous channels called nuclear pore complexes (NPCs). Translocation through the NPC is exquisitely selective and is mediated by interactions between soluble transport carriers and insoluble NPC proteins that contain phenylalanine-glycine (FG) repeats. Although most FG nucleoporins (Nups) are organized symmetrically about the planar axis of the nuclear envelope, very few localize exclusively to one side of the NPC. We constructed Saccharomyces cerevisiae mutants with asymmetric FG repeats either deleted or swapped to generate NPCs with inverted FG asymmetry. The mutant Nups localize properly within the NPC and exhibit exchanged binding specificity for the export factor Xpo1. Surprisingly, we were unable to detect any defects in the Kap95, Kap121, Xpo1, or mRNA transport pathways in cells expressing the mutant FG Nups. These findings suggest that the biased distribution of FG repeats is not required for major nucleocytoplasmic trafficking events across the NPC.
Tumor cell traffic through the extracellular matrix is controlled by the membrane-anchored collagenase MT1-MMP
Authors: Sabeh Farideh , Ota Ichiro , Holmbeck Kenn , Birkedal-Hansen Henning , Soloway Paul , Balbin Milagros , Lopez-Otin Carlos , Shapiro Steven , Inada Masaki , Krane Stephen , Allen Edward , Chung Duane , Weiss Stephen J.
Published: November 2004

As cancer cells traverse collagen-rich extracellular matrix (ECM) barriers and intravasate, they adopt a fibroblast-like phenotype and engage undefined proteolytic cascades that mediate invasive activity. Herein, we find that fibroblasts and cancer cells express an indistinguishable pericellular collagenolytic activity that allows them to traverse the ECM. Using fibroblasts isolated from gene-targeted mice, a matrix metalloproteinase (MMP)–dependent activity is identified that drives invasion independently of plasminogen, the gelatinase A/TIMP-2 axis, gelatinase B, collagenase-3, collagenase-2, or stromelysin-1. In contrast, deleting or suppressing expression of the membrane-tethered MMP, MT1-MMP, in fibroblasts or tumor cells results in a loss of collagenolytic and invasive activity in vitro or in vivo. Thus, MT1-MMP serves as the major cell-associated proteinase necessary to confer normal or neoplastic cells with invasive activity.
Condensin restructures chromosomes in preparation for meiotic divisions
Authors: Chan Raymond C. , Severson Aaron F. , Meyer Barbara J.
Published: November 2004

The production of haploid gametes from diploid germ cells requires two rounds of meiotic chromosome segregation after one round of replication. Accurate meiotic chromosome segregation involves the remodeling of each pair of homologous chromosomes around the site of crossover into a highly condensed and ordered structure. We showed that condensin, the protein complex needed for mitotic chromosome compaction, restructures chromosomes during meiosis in Caenorhabditis elegans. In particular, condensin promotes both meiotic chromosome condensation after crossover recombination and the remodeling of sister chromatids. Condensin helps resolve cohesin-independent linkages between sister chromatids and alleviates recombination-independent linkages between homologues. The safeguarding of chromosome resolution by condensin permits chromosome segregation and is crucial for the formation of discrete, individualized bivalent chromosomes.
Intratympanic Gentamicin for Menière's Disease: a Meta‐Analysis
Authors: Cohen‐Kerem Raanan , Kisilevsky Vitaly , Einarson Thomas R. , Kozer Eran , Koren Gideon , Rutka John A.
Published: November 2004

Objectives: To systematically review the published experience on intratympanic gentamicin treatment for intractable Menière's disease.

Study Design: Meta‐analysis using a random effect model.

Methods: A comprehensive literature search was performed for articles using intratympanic gentamicin as a sole treatment modality with reporting of results according to the American Academy of Otolaryngology Head and Neck Surgery (AAO‐HNS) guidelines for Menière's disease. Two reviewers independently assessed trial quality and extracted data.

Results: Fifteen trials with 627 patients met the inclusion criteria. All trials reported “before‐after” outcome measures, using patients as their own controls. No double‐blind or blinded prospective control trials were identified. Complete (class A) vertigo control was achieved in 74.7% (confidence interval [CI]95% 67.8–81.5%) of patients, and complete or substantial (class B) control was achieved in 92.7% (CI95% 89.5–96.0%). The success rate was not affected by gentamicin treatment regimen (fixed vs. titration). Hearing level and word recognition were not adversely affected, regardless of gentamicin treatment regimen. Analysis of functional level was not performed because of lack of data in the selected articles.

Conclusions: Intratympanic gentamicin treatment for intractable Menière's disease appears to be effective in the relief of vertigo. Cochleotoxicity and ototoxicity is unlikely to be a major side effect. However, the level of evidence reflected from the eligible articles is insufficient, especially because of relatively poor study design. Therefore, it is prudent that patients eligible for this type of treatment should be selected carefully and titrated with low‐dose gentamicin. Further investigation with this treatment modality with control subjects is warranted.
Prevalence and Epidemiology of Hepatitis C Virus in Patients with Squamous Cell Carcinoma of the Head and Neck
Authors: Nobles James , Wold Christian , Fazekas‐May Mary , Gilbert Jill , Friedlander Paul L.
Published: November 2004

Objective: Recently, we have noticed that a large number of patients with squamous cell carcinoma of the head and neck (SCCHN) are also infected with the hepatitis C virus (HCV). A review of the literature has revealed no published studies examining this association. The objective of this study was to determine the incidence and epidemiology of HCV infection in patients with SCCHN.

Study Design: A retrospective chart review.

Methods: Patients diagnosed with SCCHN were analyzed to determine whether they were screened for HCV. Patients were then stratified into two groups (HCV positive and HCV negative). The patient's age at onset, site and stage of the tumor at presentation were determined, and statistical analysis was performed.

Results: Ninety‐nine (26%) patients were screened, and 21 (21.2%) were HCV positive. This incidence was increased when compared with previously published data (9.9%) (P < .0038). HCV‐positive patients presented at an earlier age (51 years) versus the HCV‐negative group (60 years) (P < .0002). There were no significant differences in the site or stage at presentation.

Conclusions: In this study, 21% of patients diagnosed with SCCHN were found to be infected with HCV. These patients presented at an earlier age but had similar presentation with respect to site and stage. More research is needed to determine the significance of HCV infection in this patient population.
Assessment of Gene Expression in Head and Neck Carcinoma Using Laser Capture Microdissection and Real‐Time Reverse Transcription Polymerase Chain Reaction
Authors: Malhotra Pramit S. , Malekfzali Ashi , Bonner Robert F. , Juhn Steven , Van Waes Carter , Chen Zhong
Published: November 2004

Objectives: To quantify gene expression in tumor cells from human head and neck squamous cell carcinomas (HNSCC) using laser capture microdissection (LCM).

Study Design: Histopathologically identified HNSCC cells were microdissected from frozen sections, RNA was isolated, and vascular endothelial growth factor (VEGF) gene expression was measured by real‐time reverse transcriptase polymerase chain reaction (RT‐PCR).

Materials and Methods: Two human HNSCC tumor samples and matched normal mucosal biopsies and five human xenograft tumor specimens were harvested, embedded, and frozen in OCT. The frozen tumors were sectioned to 8 to 10 μm in thickness, and hematoxylin‐eosin (H&E) staining was performed before LCM. An estimated 2,000 to 3,000 tumor cells were microdissected from frozen sections and processed for RNA isolation. mRNA for VEGF was analyzed by real time RT‐PCR (TaqMan) with commercially available primers and probes.

Results: Two thousand to 3000 cells were necessary to obtain a suitable quantity of RNA for subsequent gene expression study by real‐time RT‐PCR. The gene expression of VEGF, a major tumor angiogenic factor, was tested in microdissected HNSCC and compared with uninvolved normal mucosal controls. A greater than seven‐fold increase of VEGF expression in tumor specimens versus mucosal controls was observed.

Conclusions: LCM is a novel sample conserving technique that allows the precise selection of tumor cells from a heterogeneous architecture. The combination of LCM and real‐time RT‐PCR appears particularly efficacious for studying HNSCC molecular pathogenesis and identifying tissue‐specific biomarkers.
Hearing Loss in Union Army Veterans from 1862 to 1920
Authors: Sewell Ryan K. , Song Chen , Bauman Nancy M. , Smith Richard J. H. , Blanck Peter
Published: November 2004

Objectives: To examine the prevalence of hearing loss (HL) in Union Army (UA) veterans by year, birth cohort, and occupation, and to compare Civil War pension and contemporary disability programs by examining monthly dollar awards.

Study Design: A retrospective review of medical records for 17,722 UA veteran pension applicants, a subset of some 35,000 soldiers retrieved randomly from the Military Archives.

Methods: The diagnosis of HL was based on review of medical records, which used gross measurements because of the unavailability of audiometric testing.

Results: One third (5,891 or 33%) of pensioners sampled received compensation for HL. The veterans with HL suffered predominantly from left‐sided HL (4,091 or 70%), which is consistent with noise‐induced HL in a right‐handed individual firing a rifle. Comparison of civilian occupations reveals minimal variation in prevalence of HL. Civil War pensions for unilateral HL averaged $134.04 per year, representing nearly one third of the average annual income in 1890. Bilateral HL received nearly twice that amount. Today, military veterans receive $1,248 annually for unilateral loss and $27,288 annually for bilateral loss. Social Security disability benefits are granted only for bilateral HL, with an average 60‐year‐old individual receiving $11,400 per year.

Conclusion: HL was a common disability among UA Civil War veterans, with noise exposure a likely etiology for the HL. The differing levels of compensation for HL may reflect differing perceptions on the incapacitating effects of HL.
Therapeutic Potential of Growth Factors for Aging Voice
Authors: Hirano Shigeru , Bless Diane M. , del Río Alejandro Muñoz , Connor Nadine P. , Ford Charles N.
Published: November 2004

Objectives/Hypothesis: It has been reported that in aged vocal folds, dense collagen deposition takes place and hyaluronic acid decreases in the lamina propria, which are thought to contribute to the vocal problems occurring with age (presbyphonia). To restore aged vocal folds to their younger state, it seems crucial to address these age‐related lamina propria changes. Intervention that might increase hyaluronic acid and decrease collagen would appear to be a potentially useful approach. The present study examined the effects of growth factors on aged fibroblasts in terms of the production of hyaluronic acid and collagen type I.

Study Design: In vitro study using animal model.

Methods: Fibroblasts were harvested from young and aged rat vocal folds and cultured with or without hepatocyte growth factor and/or basic fibroblast growth factor at different concentrations. Subsequently, the production of hyaluronic acid and collagen type I was examined in the supernatant culture media using enzyme‐linked immunosorbent assay.

Results: Aged fibroblasts produced less hyaluronic acid than younger fibroblasts. When aged and young fibroblasts were cultured with basic fibroblast growth factor, hyaluronic acid production increased and collagen type I production decreased regardless of the concentration, whereas the effects of hepatocyte growth factor appeared to vary with concentration. The basic fibroblast growth factor also was associated with stimulation of growth of aged fibroblasts.

Conclusion: The present results suggest that growth factors, especially basic fibroblast growth factor, may have therapeutic potential in restoration of aged vocal fold.
Vestibular Evoked Myogenic Potentials in Acute Low‐Tone Sensorineural Hearing Loss
Authors: Wu Chin‐Lung , Young Yi‐Ho
Published: November 2004

Objective/Hypothesis: It was the authors' premise that the vestibular evoked myogenic potential (VEMP) test may be used to differentiate acute low‐tone hearing loss (ALHL) from Menière's disease with low‐tone HL.

Study Design: Prospective study.

Methods: From January 2000 to December 2002, consecutive 12 patients with ALHL and another 12 patients with definite Menière's disease with low‐tone HL were enrolled in this study. All patients underwent audiometry and VEMP test, before and after treatment with isosorbide for 3 consecutive months.

Results: Before treatment, 12 patients with ALHL revealed normal VEMPs (11, 92%) and augmented VEMPs (1). After treatment, 11 (92%) patients had resolved to normal hearing within 3 days. One year later, two (17%) patients progressed to Menière's disease. In comparison with Menière's disease, 6 (50%) of 12 patients showed normal VEMPs before treatment, and 7 (58%) patients had their hearing improved 3 months after treatment. Comparison of VEMP responses or hearing outcome between both groups exhibited significant differences.

Conclusion: Most patients with ALHL reveal normal VEMPs throughout the episode, indicating that the saccule is spared. In contrast, 50% of Menière's disease patients with low‐tone HL demonstrate abnormal VEMPs, showing a significant difference. Therefore, the VEMP test can be used to differentiate ALHL from Menière's disease with low‐tone HL.
Evaluation of Recurrent Nerve Paralysis due to Thoracic Aortic Aneurysm and Aneurysm Repair
Authors: Ishii Kosuke , Adachi Hideo , Tsubaki Keiju , Ohta Yasushi , Yamamoto Masanori , Ino Takashi
Published: November 2004

Objectives: We sought to clarify the relationship between the outcome of recurrent laryngeal nerve paralysis with the characteristics of the thoracic aortic aneurysm and the surgical procedure used in each patient.

Methods: Nine patients who developed recurrent nerve paralysis (nonsurgical paralysis) due to a thoracic aortic aneurysm alone and 14 patients who underwent artificial vessel replacement for thoracic aortic aneurysm and developed recurrent nerve paralysis postoperatively (surgical paralysis) were evaluated.

Results: In the patients with nonsurgical paralysis, the aneurysms were similar in size to those of other patients who underwent surgery of the thoracic aorta and were invariably located near the aortic arch. Aneurysm shape was not associated with nerve paralysis. Surgical paralysis was alleviated in two patients. Surgical paralysis was observed in 9% of those who underwent surgery of the thoracic aorta. Vocal cord mobility recovered in 4 of the 11 patients with surgical paralysis who underwent follow‐up. Symptoms were alleviated by rehabilitation in many patients who did not recover vocal cord mobility. The positions of the artificial vessel anastomoses are thought to be closely related to the outcome of paralysis.

Conclusion: Recurrent nerve paralysis reduced not only the patient's quality of life but also survival by leading to disorders including aspiration pneumonia. Therefore, early rehabilitation should be performed, and surgical treatment should be considered, if necessary, for patients with recurrent nerve paralysis.
Treatment of Olfactory Dysfunction, II: Studies With Minocycline
Authors: Kern R C. , Conley D B. , Haines G K. , Robinson A M.
Published: November 2004

Objectives/Hypothesis: The treatment of anosmia has changed minimally since the early 1970s, despite dramatic advances in the understanding of the molecular biology of olfaction. Recent studies from the authors' laboratory have suggested that most common causes of clinical olfactory dysfunction, including rhinosinusitis, appear to be associated with increased apoptotic death of olfactory sensory neurons. This appears to result in a decline in the number of functioning mature olfactory sensory neurons, despite the capacity of the olfactory epithelium for regeneration. The current study evaluated the ability of the antibiotic minocycline to inhibit olfactory sensory neuron apoptosis. This drug is known to inhibit apoptosis separate from its anti‐infective properties. Olfactory sensory neuron apoptosis was triggered by surgical deafferentation (“bulbectomy”), the standard experimental model. Earlier studies have indicated that bulbectomy and sinusitis invoke similar proteolytic enzyme cascades in olfactory sensory neurons.

Study Design: Histological analysis of animal olfactory tissue.

Methods: Mice underwent unilateral olfactory bulbectomy to induce apoptotic olfactory sensory neuron death, with and without 45 mg/kg intraperitoneal minocycline given 12 hours before surgery and every 12 hours until death. Mice were killed at 2 and 4 days after bulbectomy and assessed for activation of capsase‐3 and olfactory sensory neuron survival by immunohistochemical analysis.

Results: Minocycline resulted in partial suppression of cell death at 2 days after surgery when compared with untreated animals.

Conclusion: Minocycline inhibits olfactory sensory neuron death in the face of a potent pro‐apoptotic stimulus. This drug is well tolerated and is currently undergoing human trials for the management of a variety of neurological disorders associated with apoptosis. The current results suggest that minocycline may be efficacious in the management of peripheral olfactory loss as well.
The Woman behind Frey's Syndrome: The Tragic Life of Lucja Frey
Authors: Moltrecht Mirjam , Michel Olaf
Published: November 2004

Objective: The auriculotemporal syndrome is known worldwide as Frey's syndrome. However, the Jewish physician Lucja Frey, after whom it was named, has fallen into obscurity. The little information about her is fragmentary, contradictory, and often incorrect.

Study Design: To reconstruct the life of Lucja Frey, who was murdered by the Nazis in her native town if Lwów, it was imperative to look for original documents as irrevocable proof of her life.

Methods: During this research, more than 100 archives and institutions in 8 countries have been contacted.

Results: With the archive materials, it was possible for the first time to create a complete picture of the life of this fascinating physician. Furthermore, her day of death, unknown until now, could be determined with great plausibility. The lasting impression is not only of a tragic death under the Nazis but also of a tragic life as a whole.

Conclusion: Lucja Frey would have been forgotten if not for the eponym Frey's syndrome. In this way, she is remembered not only as an unusual woman, physician, and scientist but also as one of millions of Jews murdered by the Nazis. This may be the only key remaining to prevent the repetition of one of the most haunting and devastating times in history.
Bronchogenic Cyst Presenting as a Symptomatic Neck Mass in an Adult: Case Report and Review of the Literature
Authors: Al‐kasspooles Mazin F. , Alberico Ronald A. , Douglas Wade G. , Litwin Alan M. , Wiseman Sam M. , Rigual Nestor R. , Loree Thom R. , Hicks Wesley L.
Published: November 2004

We report the unusual clinical manifestation and subsequent management of a symptomatic congenital bronchogenic cyst that connected to the trachea and presented in the neck of an adult. The embryology, clinical presentation, diagnostic evaluation, and management options of this rare aberration are discussed.
Cochlear Implantation in Patients with Substantial Residual Hearing
Authors: Cullen Robert D. , Higgins Carol , Buss Emily , Clark Marcia , Pillsbury Harold C. , Buchman Craig A.
Published: November 2004

Objectives: Cochlear implantation is an effective means for providing auditory rehabilitation in adult patients with severe to profound sensorineural hearing loss. It has been hypothesized that patients with substantial, preoperative residual hearing would be excellent cochlear implant candidates because of surviving neural populations and a lack of auditory deprivation. The purpose of this study is to describe the outcomes of patients with substantial residual hearing who have undergone cochlear implantation.

Study Design: Retrospective chart review of patients with substantial preoperative residual hearing who underwent cochlear implantation.

Methods: Chart reviews were completed for patients with substantial residual hearing who underwent cochlear implantation (City University of New York Sentence Test [CUNY] > 60%, Hearing in Noise Test sentences presented in quiet [HINTQ] > 50%, or Consonant‐Nucleus‐Consonant [CNC] > 20% in the ear to be implanted). Preoperative and postoperative measures of audiologic performance as well as complications were assessed.

Results: All 12 patients who met inclusion criteria ultimately surpassed their preoperative aided performance level after implantation and gained significant benefit from their cochlear implant. At 6 months postimplantation, mean CUNY, HINTQ, and CNC scores were 93%, 78%, and 48% in the implant ear alone, respectively. However, progress was slower than expected for many patients, and at least one patient took 1 year to surpass his preoperative performance level. There were no complications from surgery in this selected group of patients.

Conclusions: Patients with some degree of residual hearing do benefit from cochlear implantation. However, there may be an initial decline in performance as compared with preoperative levels. This decline is overcome in time in this patient population. These patients need to be counseled accordingly.