bluuebunny/crossref_metadata_2025 huggingface dataset:
A Functional Magnetic Resonance Imaging Investigation of Verbal Working Memory in Adolescents With Specific Language Impairment
Authors: Weismer Susan Ellis , Plante Elena , Jones Maura , Tomblin J. Bruce
Published: April 2006

This study used neuroimaging and behavioral techniques to examine the claim that processing capacity limitations underlie specific language impairment (SLI). Functional magnetic resonance imaging (fMRI) was used to investigate verbal working memory in adolescents with SLI and normal language (NL) controls. The experimental task involved a modified listening span measure that included sentence encoding and recognition of final words in prior sets of sentences. The SLI group performed significantly poorer than the NL group for both encoding and recognition and displayed slower reaction times for correct responses on high complexity encoding items. fMRI results revealed that the SLI group exhibited significant hypoactivation during encoding in regions that have been implicated in attentional and memory processes, as well as hypoactivation during recognition in regions associated with language processing. Correlational analyses indicated that adolescents with SLI exhibited different patterns of coordinating activation among brain regions relative to controls for both encoding and recognition, suggesting reliance on a less functional network. These findings are interpreted as supporting the notion that constraints in nonlinguistic systems play a role in SLI.
The Expression of Aspect in Cantonese-Speaking Children With Specific Language Impairment
Authors: Fletcher Paul , Leonard Laurence B. , Stokes Stephanie F. , Wong Anita M.-Y.
Published: April 2006

Previous studies of verb morphology in children with specific language impairment (SLI) have been limited in the main to tense and agreement morphemes. Cantonese, which, like other Chinese languages, has no grammatical tense, presents an opportunity to investigate potential difficulties for children with SLI in other areas of verb morphology, via scrutiny of elements of its aspectual system. The performance of 3 groups of children (
n
=15 in each group)—preschoolers with SLI, typically developing same-age peers, and younger, typically developing peers—was compared in procedures designed to elicit aspect forms. The children with SLI were less likely to produce both perfective and imperfective aspect markers. It is suggested that reasons for these findings are to be found in the sparse morphology of Cantonese and in the nonobligatory nature of these forms.
Impact of Aberrant Acoustic Properties on the Perception of Sound Quality in Electrolarynx Speech
Authors: Meltzner Geoffrey S. , Hillman Robert E.
Published: April 2006

A large percentage of patients who have undergone laryngectomy to treat advanced laryngeal cancer rely on an electrolarynx (EL) to communicate verbally. Although serviceable, EL speech is plagued by shortcomings in both sound quality and intelligibility. This study sought to better quantify the relative contributions of previously identified acoustic abnormalities to the perception of degraded quality in EL speech. Ten normal listeners evaluated the sound quality of EL speech tokens that had been acoustically enhanced by (a) increased low-frequency energy, (b) EL-noise reduction, and (c) fundamental frequency variation to mimic normal pitch intonation in relation to nonenhanced EL speech, normal speech, and normal monotonous speech (fundamental frequency variation removed). In comparing all possible combinations of token pairs, listeners were asked to identify which one of each pair sounded most like normal natural speech, and then to rate on a visual analog scale how different the chosen token was from normal speech. The results indicate that although EL speech can be most improved by removing the EL noise and providing proper pitch information, the resulting quality is still well below that of normal natural speech or even that of monotonous natural speech. This suggests that, in addition to the widely acknowledged acoustic abnormalities examined in this investigation, there are other attributes that contribute significantly to the unnatural quality of EL speech. Such additional factors need to be clearly identified and remedied before EL speech can be made to more closely approximate the sound quality of normal natural speech.
Perception of Spectral Contrast by Hearing-Impaired Listeners
Authors: Dreisbach Laura E. , Leek Marjorie R. , Lentz Jennifer J.
Published: April 2006

The ability to discriminate the spectral shapes of complex sounds is critical to accurate speech perception. Part of the difficulty experienced by listeners with hearing loss in understanding speech sounds in noise may be related to a smearing of the internal representation of the spectral peaks and valleys because of the loss of sensitivity and an accompanying reduction in frequency resolution. This study examined the discrimination by hearing-impaired listeners of highly similar harmonic complexes with a single spectral peak located in 1 of 3 frequency regions. The minimum level difference between peak and background harmonics required to discriminate a small change in the spectral center of the peak was measured for peaks located near 2, 3, or 4 kHz. Component phases were selected according to an algorithm thought to produce either highly modulated (positive Schroeder) or very flat (negative Schroeder) internal waveform envelopes in the cochlea. The mean amplitude difference between a spectral peak and the background components required for discrimination of pairs of harmonic complexes (spectral contrast threshold) was from 4 to 19 dB greater for listeners with hearing impairment than for a control group of listeners with normal hearing. In normal-hearing listeners, improvements in threshold were seen with increasing stimulus level, and there was a strong effect of stimulus phase, as the positive Schroeder stimuli always produced lower thresholds than the negative Schroeder stimuli. The listeners with hearing loss showed no consistent spectral contrast effects due to stimulus phase and also showed little improvement with increasing stimulus level, once their sensitivity loss was overcome. The lack of phase and level effects may be a result of the more linear processing occurring in impaired ears, producing poorer-than-normal frequency resolution, a loss of gain for low amplitudes, and an altered cochlear phase characteristic in regions of damage.
Are Specific Language Impairment and Dyslexia Distinct Disorders?
Authors: Catts Hugh W. , Adlof Suzanne M. , Hogan Tiffany P. , Weismer Susan Ellis
Published: April 2006

Purpose:
The purpose of this study was to determine whether specific language impairment (SLI) and dyslexia are distinct developmental disorders.

Method:
Study 1 investigated the overlap between SLI identified in kindergarten and dyslexia identified in 2nd, 4th, or 8th grades in a representative sample of 527 children. Study 2 examined phonological processing in a subsample of participants, including 21 children with dyslexia only, 43 children with SLI only, 18 children with SLI and dyslexia, and 165 children with typical language/reading development. Measures of phonological awareness and nonword repetition were considered.

Results:
Study 1 showed limited but statistically significant overlap between SLI and dyslexia. Study 2 found that children with dyslexia or a combination of dyslexia and SLI performed significantly less well on measures of phonological processing than did children with SLI only and those with typical development. Children with SLI only showed only mild deficits in phonological processing compared with typical children.

Conclusions:
These results support the view that SLI and dyslexia are distinct but potentially comorbid developmental language disorders. A deficit in phonological processing is closely associated with dyslexia but not with SLI when it occurs in the absence of dyslexia.
Visual Attention in Deaf and Normal Hearing Adults
Authors: Sladen Douglas P. , Tharpe Anne Marie , Ashmead Daniel H. , Grantham D. Wesley , Chun Marvin M.
Published: April 2006

Visual perceptual skills of deaf and normal hearing adults were measured using the Eriksen flanker task. Participants were seated in front of a computer screen while a series of target letters flanked by similar or dissimilar letters was flashed in front of them. Participants were instructed to press one buttonwhen they saw an
H
, and another buttonwhen they saw an
N
. Targets
H
and
N
were flashedwith flanking letters that were either
H
or
N
, creating response-compatible and response-incompatible arrays. Flankers were presented at different distances from the targets and reaction times were measured. In the present study, reaction times were significantly faster for the hearing group than for the deaf group. However, the hearing group had significantly more errors on this task than the deaf group, suggesting that the deaf participants may have been more deliberate in their responses. In addition, the deaf group revealed a significantly greater interference effect than the hearing group at a parafoveal (i.e., 1.0°) eccentricity. These findings suggest that deaf individuals may allocate their visual resources over a wider range than those with normal hearing.
Theory of the statistics of kinetic transitions with application to single-molecule enzyme catalysis
Authors: Gopich Irina V. , Szabo Attila
Published: April 2006

Single-molecule spectroscopy can monitor transitions between two microscopic states when these transitions are associated with the emission of photons. A general formalism is developed for obtaining the statistics of such transitions from a microscopic model when the dynamics is described by master or rate equations or their continuum analog, multidimensional reaction-diffusion equations. The focus is on the distribution of the number of transitions during a fixed observation time, the distribution of times between transitions, and the corresponding correlation functions. It is shown how these quantities are related to each other and how they can be explicitly calculated in a straightforward way for both immobile and diffusing molecules. Our formalism reduces to renewal theory when the monitored transitions either go to or originate from a single state. The influence of dynamics slow compared with the time between monitored transitions is treated in a simple way, and the probability distributions are expressed in terms of Mandel-type formulas. The formalism is illustrated by a detailed analysis of the statistics of catalytic turnovers of enzymes. When the rates of conformational changes are slower than the catalytic rates which are in turn slower than the binding relaxation rate, (1) the mean number of turnovers is shown to have the classical Michaelis-Menten form, (2) the correlation function of the number of turnovers is a direct measure of the time scale of catalytic rate fluctuations, and (3) the distribution of the time between consecutive turnovers is determined by the steady-state distribution.
A general perturbation approach for equation of state development: Applications to simple fluids, ab initio potentials, and fullerenes
Authors: Paricaud Patrice
Published: April 2006

A new perturbation scheme based on the Barker-Henderson perturbation theory [J. Chem. Phys. 47, 4714 (1967)] is proposed to predict the thermodynamic properties of spherical molecules. Accurate predictions of second virial coefficients and vapor-liquid coexistence properties are obtained for a large variety of potential functions (square well, Yukawa, Sutherland, Lennard-Jones, Buckingham, Girifalco). New Gibbs ensemble Monte Carlo simulations of the generalized exp-m Buckingham potential are reported. An extension of the perturbation approach to mixtures is proposed, and excellent predictions of vapor-liquid equilibria are obtained for Lennard-Jones mixtures. The perturbation scheme can be applied to complex potential functions fitted to ab initio data to predict the properties of real molecules such as neon. The new approach can also be used as an auxiliary tool in molecular simulation studies, to efficiently optimize an intermolecular potential on macroscopic properties or match force fields based on different potential functions.
The very unusual properties of the resolvent, heat kernel, and zeta function for the operator −d2∕dr2−1∕(4r2)
Authors: Kirsten Klaus , Loya Paul , Park Jinsung
Published: April 2006

In this paper we analyze the resolvent, the heat kernel and the spectral zeta function of the operator −d2∕dr2−1∕(4r2) over the finite interval. The structural properties of these spectral functions depend strongly on the chosen self-adjoint realization of the operator, a choice being made necessary because of the singular potential present. Only for the Friedrichs realization standard properties are reproduced, for all other realizations highly nonstandard properties are observed. In particular, for k∊N we find terms like (logt)−k in the small-t asymptotic expansion of the heat kernel. Furthermore, the zeta function has s=0 as a logarithmic branch point.
Band gap shift in the GaN∕AlN multilayers on the mesh-patterned Si(111)
Authors: Chen C.-H. , Yeh C.-M. , Hwang J. , Tsai T.-L. , Chiang C.-H. , Chang C.-S. , Chen T.-P.
Published: April 2006

The band gap shift in the 80×80μm2 crack-free GaN∕AlN multilayers on the mesh-patterned Si(111) has been characterized by cathodoluminescence (CL) and Raman techniques. The GaN band gap derived from CL spectra depends on the spatial point inside a mesh, which changes from 3.413eV (at center) to 3.418eV (at edge) and to 3.426eV (at corner). The band gap shift is attributed to the variation of tensile stress inside the mesh, confirmed by Raman mapping. The shift of GaN band gap per unit stress is determined to be 0.03eV∕GPa.
Exciton spin precessions in a biased double quantum dot
Authors: Madureira Justino R. , Degani Marcos H. , Maialle Marcelo Z.
Published: April 2006

We investigated the electric field effects on the spin precessions of excitons in a double quantum dot embedded in a semiconductor nanowire under an applied magnetic field. The electric field moves the carriers in the dots along the nanowire axis, modifying their confinement and therefore the effective g factors and the electron-hole exchange interaction. We obtain the time evolution of the excitonic spin and show, from the spin precession spectra, how the applied electric field affects the excitonic spin dynamics.
Radio-frequency characterization for the single-walled carbon nanotubes
Authors: Zhang Min , Huo Xiao , Chan Philip C. H. , Liang Qi , Tang Z. K.
Published: April 2006

Carbon nanotube (CNT) has a potential to be used as nanoscale transmission lines and as high-performance passive components in nanoelectronics. In this letter, we discuss single-walled carbon nanotubes (SWNTs) that were grown using a chemical-vapor deposition technique. Both the dc and ac two-terminal resistances were measured and analyzed. The transmission properties of the SWNTs were shown by comparing the S parameters of a device with CNTs with those of a device without a CNT. The radio-frequency characterization of the CNTs was carried out using the network analyzer to frequency of 20GHz.
Mapping the
Arabidopsis
organelle proteome
Authors: Dunkley Tom P. J. , Hester Svenja , Shadforth Ian P. , Runions John , Weimar Thilo , Hanton Sally L. , Griffin Julian L. , Bessant Conrad , Brandizzi Federica , Hawes Chris , Watson Rod B. , Dupree Paul , Lilley Kathryn S.
Published: April 2006

A challenging task in the study of the secretory pathway is the identification and localization of new proteins to increase our understanding of the functions of different organelles. Previous proteomic studies of the endomembrane system have been hindered by contaminating proteins, making it impossible to assign proteins to organelles. Here we have used the localization of organelle proteins by the isotope tagging technique in conjunction with isotope tags for relative and absolute quantitation and 2D liquid chromatography for the simultaneous assignment of proteins to multiple subcellular compartments. With this approach, the density gradient distributions of 689 proteins from
Arabidopsis thaliana
were determined, enabling confident and simultaneous localization of 527 proteins to the endoplasmic reticulum, Golgi apparatus, vacuolar membrane, plasma membrane, or mitochondria and plastids. This parallel analysis of endomembrane components has enabled protein steady-state distributions to be determined. Consequently, genuine organelle residents have been distinguished from contaminating proteins and proteins in transit through the secretory pathway.
Direct requirement for Xmus101 in ATR-mediated phosphorylation of Claspin bound Chk1 during checkpoint signaling
Authors: Yan Shan , Lindsay Howard D. , Michael W. Matthew
Published: April 2006

TopBP1-like proteins, which include Xenopus laevis Xmus101, are required for DNA replication and have been linked to replication checkpoint control. A direct role for TopBP1/Mus101 in checkpoint control has been difficult to prove, however, because of the requirement for replication in generating the DNA structures that activate the checkpoint. Checkpoint activation occurs in X. laevis egg extracts upon addition of an oligonucleotide duplex (AT70). We show that AT70 bypasses the requirement for replication in checkpoint activation. We take advantage of this replication-independent checkpoint system to determine the role of Xmus101 in the checkpoint. We find that Xmus101 is essential for AT70-mediated checkpoint signaling and that it functions to promote phosphorylation of Claspin bound Chk1 by the ataxia-telangiectasia and Rad-3–related (ATR) protein kinase. We also identify a separation-of-function mutant of Xmus101. In extracts expressing this mutant, replication of sperm chromatin occurs normally; however, the checkpoint response to stalled replication forks fails. These data demonstrate that Xmus101 functions directly during signal relay from ATR to Chk1.
Healthcare-Associated Myiasis: Prevention and Intervention
Authors: Sherman Ronald A. , Roselle Gary , Bills Carol , Danko Linda H. , Eldridge Noel
Published: April 2006

Healthcare-associated myiasis (maggot infestation) can have complications that go well beyond the medical consequences of the infestation for patients, their families, and facilities. Prevention of healthcare-associated myiasis requires effort on two fronts: minimizing patient risk factors and reducing fly populations in the healthcare environment. If myiasis occurs, intervention must be swift, thorough, and interdisciplinary. The first priority always is the well-being of the patient. Preservation and identification of the maggots can help determine the likely timing and circumstances that led to the infestation. Conditions favoring the infestation must be identified and then corrected. Free and rapid communication must be promoted. A single designated knowledgeable spokesperson to communicate with the patient, employees, and, as needed, the media will reduce mis-communication and hasten mitigation. Following the guidelines presented in this document, healthcare facilities should be able to reduce the likelihood of healthcare-associated myiasis and effectively intervene when such events occur.
Preparing for Pandemic Influenza: Should Hospitals Stockpile Oseltamivir?
Authors: Cinti Sandro , Chenoweth Carol , Monto Arnold S.
Published: April 2006

The outbreak of H5N1 avian influenza in Asia has reignited concerns about an influenza pandemic. It is clear that influenza vaccine will be in short supply (or nonexistent) early in an influenza pandemic. Without vaccine, the role of antiviral agents, especially oseltamivir, in treatment and prophylaxis is of paramount importance. Unfortunately, the government cannot possibly stockpile enough oseltamivir to provide long-term prophylaxis or treatment for every healthcare worker in the United States. We think that hospitals should consider stockpiling oseltamivir, and we provide a strategy for doing so at a reasonable cost.
Influenza Vaccination Among Healthcare Workers in a University Children's Hospital
Authors: Tapiainen Terhi , Bär Gurli , Schaad Urs B. , Heininger Ulrich
Published: April 2006

Objectives:

To evaluate the attitudes of pediatric healthcare workers (HCWs) toward influenza vaccination and to increase their rate of immunization.

Methods:

A survey was conducted among pediatric HCWs using an anonymous questionnaire. Survey results were used to design an intervention to increase the immunization rate of staff. Immunization rates before (2003-2004) and after (2004-2005) intervention were assessed using immunization clinic records.

Setting:

A university children's hospital in Switzerland.

Interventions:

(1) An informational letter based on misconceptions noted in the survey, (2) educational conversations with head nurses, (3) more “walk-in” immunization clinics, and (4) a direct offer of influenza immunization on the wards.

Results:

Among vaccine nonrecipients, doubts about the efficacy and necessity of influenza immunization were prevalent and more often reported by nurses than physicians (75% vs 41%, P = .002; and 55% vs 23%, P = .001, respectively). Physicians more often than nurses reported lack of time as a reason for not receiving influenza vaccination (23% vs 5%, P = .01). After intervention, the immunization rate of HCWs increased from 19% to 24% (P = .03). The immunization rate of physicians increased from 43% to 64% (P = .004). No change was noted among nurses (13% vs 14%) and other HCWs (16% vs 16%).

Conclusions:

Misconceptions about influenza vaccination were prevalent among pediatric staff, particularly nurses. Active promotion and educational efforts were successful in increasing the immunization rate of physicians but not nurses and other HCWs.
Electron transfer to nitrite reductase of Rhodobacter sphaeroides 2.4.3: examination of cytochromes c 2 and c Y
Authors: Laratta William P. , Nanaszko Michael J. , Shapleigh James P.
Published: April 2006

The role of cytochromec2, encoded bycycA, and cytochromecY, encoded bycycY, in electron transfer to the nitrite reductase ofRhodobacter sphaeroides2.4.3 was investigated using bothin vivoandin vitroapproaches. BothcycAandcycYwere isolated, sequenced and insertionally inactivated in strain 2.4.3. Deletion of either gene alone had no apparent effect on the ability ofR. sphaeroidesto reduce nitrite. In acycA–cycYdouble mutant, nitrite reduction was largely inhibited. However, the expression of the nitrite reductase genenirKfrom a heterologous promoter substantially restored nitrite reductase activity in the double mutant. Using purified protein, a turnover number of 5 s−1was observed for the oxidation of cytochromec2by nitrite reductase. In contrast, oxidation ofcYonly resulted in a turnover of ∼0·1 s−1. The turnover experiments indicate thatc2is a major electron donor to nitrite reductase butcYis probably not. Taken together, these results suggest that there is likely an unidentified electron donor, in addition toc2, that transfers electrons to nitrite reductase, and that the decreased nitrite reductase activity observed in thecycA–cycYdouble mutant probably results from a change innirKexpression.
d-Galactose induces cellulase gene expression in Hypocrea jecorina at low growth rates
Authors: Karaffa Levente , Fekete Erzsébet , Gamauf Christian , Szentirmai Attila , Kubicek Christian P. , Seiboth Bernhard
Published: April 2006

Lactose (1,4-O-β-d-galactopyranosyl-d-glucose) is a soluble and economic carbon source for the industrial production of cellulases or recombinant proteins by Hypocrea jecorina (anamorph Trichoderma reesei). The mechanism by which lactose induces cellulase formation is not understood. Recent data showed that the galactokinase step is essential for cellulase induction by lactose, but growth on d-galactose alone does not induce cellulases. Consequently, the hypothesis was tested that d-galactose may be an inducer only at a low growth rate, which is typically observed when growing on lactose. Carbon-limited chemostat cultivations of H. jecorina were therefore performed at different dilution rates with d-galactose, lactose, galactitol and d-glucose. Cellulase gene expression was monitored by using a strain carrying a fusion between the cbh2 (encoding cellobiohydrolase 2, Cel6A) promoter region and the Aspergillus niger glucose oxidase gene and by identification of the two major cellobiohydrolases Cel7A and Cel6A. The results show that d-galactose indeed induces cbh2 gene transcription and leads to Cel7A and Cel6A accumulation at a low (D=0·015 h−1) but not at higher dilution rates. At the same dilution rate, growth on d-glucose did not lead to cbh2 promoter activation or Cel6A formation but a basal level, lower than that observed on d-galactose, was detected for the carbon-catabolite-derepressible Cel7A. Lactose induced significantly higher cellulase levels at 0·015 h−1 than d-galactose and induced cellulases even at growth rates up to 0·042 h−1. Results of chemostats with an equimolar mixture of d-galactose and d-glucose essentially mimicked the behaviour on d-galactose alone, whereas an equimolar mixture of d-galactose and galactitol, the first intermediate of a recently described second pathway of d-galactose catabolism, led to cellulase induction at D=0·030 h−1. It is concluded that d-galactose indeed induces cellulases at low growth rate and that the operation of the alternative pathway further increases this induction. However, under those conditions lactose is still a superior inducer for which the mechanism remains to be clarified.
Awake fibrecapnic intubation: a novel technique for intubation in head and neck cancer patients with a difficult airway*
Authors: Huitink J. M. , Buitelaar D. R. , Schutte P. F. E.
Published: April 2006

Awake fibreoptic intubation is the gold standard for difficult airway management but failures are reported in the literature in up to 13% of cases. In case of failure, a tracheotomy is often indicated. We describe a novel technique for intubation in head and neck cancer patients with a difficult airway that we call awake fibrecapnic intubation. The aim of this study was to investigate the feasibility of this technique. We studied prospectively 15 consecutive intubations in head and neck cancer patients before diagnostic or therapeutic surgical procedures. After topical anaesthesia, a fibrescope was introduced into the pharynx. Spontaneous respiration was maintained in all patients. Through the suction channel of the fibrescope a special suction catheter was advanced into the airway for carbon dioxide measurements. When four capnograms were obtained, the fibrescope was railroaded over the catheter and after identification of tracheal rings, a tracheal tube was placed. Tracheal intubation was successful in all patients without bleeding or complications, with a median (range) time to intubation of 3 (2–15) min. Identification of the vocal cords and glottis was difficult in four patients due to extensive anatomical abnormalities or poor visibility; even in these patients, a capnogram was obtained within 4 s.
Effects of smoking on cardiopulmonary baroreceptor activation and peripheral vascular resistance
Authors: Arosio E. , De Marchi S. , Rigoni A. , Prior M. , Lechi A.
Published: April 2006

Patients and Methods  We studied 16 healthy smokers and 16 nonsmokers acting as controls. We subjected smokers and nonsmokers to cardiopulmonary baroreceptor stimulation by studying forearm and common carotid haemodynamic and sympathovagal balance. Smokers repeated the tests after smoking one cigarette. Smokers and controls were subjected to passive elevation of the legs and the trunk in a horizontal position with pressure monitoring and measurement of the calibre and flow in the brachial and common carotid arteries using a colourDoppler ultrasound. We calculated forearm resistance and carotid wall tension. We also studied R‐R variability, calculating the ratio between low frequency (LF) and high frequency (HF) R‐R interval variability.

Results  During stimulation diastolic blood pressure values decreased in controls and in smokers at rest. After smoking one cigarette, smokers showed an increase in systolic and diastolic blood pressure as well as in the heart rate during stimulation. Humeral artery increased the calibre during stimulation in both groups; after cigarette smoking the calibre declined throughout the study phases. Forearm resistance decreased in both groups during stimulation at rest, but increased after cigarette smoking. The LF/HF ratio decreased during stimulation in both groups, and it increased at rest after smoking. Carotid diameter did not change in either group, and wall tension increased in smokers after smoking one cigarette.

Conclusions  Smoking one cigarette increases resistance, impairs baroreflex and increases carotid wall tension in mild smokers. These findings may explain the higher rate of a cardiovascular event in smokers.
The specific JNK inhibitor SP600125 targets tumour necrosis factor‐α production and epithelial cell apoptosis in acute murine colitis
Authors: Assi Kiran , Pillai Rex , Gómez‐Muñoz Antonio , Owen David , Salh Baljinder
Published: April 2006

Stress‐activated protein kinases (SAPKs) are activated in human inflammatory bowel disease (IBD). Recently it has been demonstrated that p38MAPK (mitogen‐activated protein kinase) inhibition using SB203580 is effective in reducing disease in both dextran sulphate sodium (DSS)‐induced and 2,4,6‐trinitrobenzenesulphonic acid (TNBS)‐induced murine colitides, underscoring the importance of this pathway in gastrointestinal inflammation. However, the contribution of c‐Jun N‐terminal kinase (JNK) in intestinal inflammation is unknown. Based on the known involvement of JNK in tumour necrosis factor‐α (TNF‐α) expression and in mediating the effects of oxidant stress, we hypothesized that JNK inhibition would also affect colitis. Our studies in mice with DSS‐induced colitis treated with the JNK inhibitor SP600125, indicate that there is a significant reduction in wasting as well as a significant reduction in histological damage scores. Both total colonic and mesenteric lymphocyte CD3/CD28‐stimulated TNF‐α levels were dramatically reduced under the same circumstances. This was associated with a reduction in JNK protein expression and activity, as well as a reduction in AP‐1 DNA binding with SP600125. Interestingly, there were no apparent changes in either p38MAPK or p42/44ERKs. Immunofluorescence of the colon for the active form of JNK revealed a prominent signal arising from the infiltrating inflammatory cells. SP600125 reduced this as well as, specifically, macrophage infiltration. Strikingly, we also demonstrate reduced epithelial cell apoptosis in response to treatment with SP600125. We conclude that specific inhibition of JNK is beneficial in the DSS model of colitis, and may be of value in human IBD.
An unusual case of massive gastric distension with catastrophic sequelae
Authors: Lewis S. , Holbrook A. , Hersch P.
Published: April 2006

We report a case of massive gastric distension presenting with abdominal pain, shock and lower limb ischaemia. At laparotomy, gastric distension was found to be secondary to gastric outflow obstruction compounded by gas formation from antacid ingestion. Both the aorta and inferior vena cava were directly compressed by the distended stomach. This mode of presentation and combined aetiologies remain unreported. Gastric decompression resulted in profound cardiovascular compromise, multiorgan failure and eventually death.
Effects of Bt‐toxin Cry1Ac on Propylaea japonica Thunberg (Col., Coccinellidae) by feeding on Bt‐treated Bt‐resistant Helicoverpa armigera (Hübner) (Lep., Noctuidae) larvae
Authors: Zhang S.‐Y. , Li D.‐M. , Cui J. , Xie B.‐Y.
Published: April 2006

Abstract:  Propylaea japonica is an important predatory insect of common cotton pests. To assess the ecological effects of transgenic Bt cotton, expressing Cry1Ac toxin, on this predator, we examined the life history parameters of P. japonica for two generations by feeding them with Bt‐resistant Helicoverpa armigera. After ingesting Bt‐treated Bt‐resistant H. armigera larvae in the third and fourth instar, the body mass and body length of adult P. japonica decreased, a combined effect of poor prey quality and Cry1Ac Bt‐toxin may account for these effects. However, larval survivorship and development in these two instars, pupal mortality, fecundity and adult longevity of P. japonica were not affected in both the generations. These results suggest that ingesting Bt‐toxin Cry1Ac‐treated pests in advanced larval stage might have no significant effect on the fitness of predator P. japonica.
Potential for mating disruption to reduce cone damage by the spruce seed moth, Cydia strobilella, in spruce seed orchards
Authors: Trudel R. , Guertin C. , Grant G. G.
Published: April 2006

Abstract:  The spruce seed moth, Cydia strobilella (L.), is a serious and widely distributed pest of spruce seed orchards in North America and Europe. Current pest management activities in seed orchards rely mainly on chemical pesticides for insect control. Mating disruption with sex pheromone is a potential alternative pest management tool for C. strobilella. In 2002, field tests confirmed that sticky traps baited with 3 μg of (E)‐8‐dodencenyl acetate (E8‐12:Ac), the sex pheromone of C. strobilella, could capture males in Quebec, a region of Canada not previously monitored for this insect. In the following years (2003–2005), grey rubber septa loaded with 0.75, 1.5, or 2.0 mg of E8‐12:Ac were deployed separately in two white spruce seed orchards at a density of 40 and 60 dispensers/ha to test the potential for mating disruption. The results showed that the captures of male C. strobilella in the pheromone‐treated plots were reduced by up to 98%. Furthermore, at the end of the experiment in 2005, 17.3% of cones were damaged by C. strobilella in the treated plot, compared with a significantly (P < 0.0001) higher 56.4% in the control plot. The results suggest that mating disruption has potential for controlling C. strobilella to protect seed cones in white spruce seed orchards.
Lizards and termites revisited
Authors: COLLI GUARINO R. , CONSTANTINO REGINALDO , COSTA GABRIEL C.
Published: April 2006

Abstract  We evaluate the hypothesis, originally proposed for arid Australia, that abundant and diverse termite assemblages can promote lizard radiation, based on a reappraisal of published data and on new data from the Cerrado biome in central Brazil. We found a positive correlation between termite and lizard richness in Cerrado. However, termite abundance and richness cannot actively drive lizard speciation, but can be important in maintaining lizard richness. Cerrado shares with arid Australia a rich and abundant termite fauna, but local Cerrado lizard assemblages are relatively impoverished. We suggest that differences in lizard richness between Cerrado and arid Australia may be explained by a combination of variations in area and latitude controlling speciation rates and present‐day ecological factors moderating extinction rates.
ROMAN REPLICATIONS OF GREEK ART AT THE VILLA DELLA FARNESINA
Authors: WYLER STÉPHANIE
Published: April 2006

The decoration of the Villa of the Farnesina, designed in early Augustean Rome, displays a complex system of artistic and religious references to Greek culture. By means of an eclectic collection of artistic replications and emulations spread out through art galleries painted in trompe l'oeil, artists and owner reached a new style based on the appropriation of the conquered world, very carefully organized into a cultural hierarchy. The arts of classical Athens, embodied not only stylistically, but also thematically, are reproduced as framed pictures, whereas those of Hellenistic Egypt are integrated into the imitation of architecture. Dionysiac imagery functions as a paradigm of this system, at least in the preserved part of the villa: instead of losing divine prestige after Augustus's victory at Actium and his assumption of sole power in 31 BCE, Dionysos appears as one of the main keys to the whole decoration – as a sign of Greek cultures, assimilated for their familiar exoticism, into the new imperial language.
Disclosure and Secrecy in Adolescent–Parent Relationships
Authors: Smetana Judith G. , Metzger Aaron , Gettman Denise C. , Campione‐Barr Nicole
Published: April 2006

Beliefs about parents' legitimate authority and adolescents' obligations to disclose to parents and actual disclosure and secrecy in different domains were examined in 276 ethnically diverse, lower middle‐class 9th and 12th graders (Ms=14.62 and 17.40 years) and their parents (n=249). Adolescents were seen as more obligated to disclose prudential issues and less obligated to disclose personal than moral, conventional, and multifaceted issues; parents viewed adolescents as more obligated to disclose to parents than adolescents perceived themselves to be. Adolescents disclosed more to mothers than to fathers, particularly regarding personal issues, but mothers overestimated girls' disclosure. Greater trust, perceived obligations to disclose, and, for personal issues, more parental acceptance and psychological control predicted more disclosure and less secrecy.
Photomaximization test for identifying photoallergic contact sensitizers
Authors: Kaidbey Kays H. , Kligman Albert M.
Published: April 2006

The photomaximization procedure was designed to identify topical photocontact sensitizers following the format of the maximization test for contact sensitizers. The test agent is applied for 24 hours followed by exposure to three Minimal Erythema Doses (MED) of solar simulated radiation twice weekly for 3 weeks (six exposures) in a panel of 25 white Caucasoids.

The subjects are challenged 2 weeks later with 4.0 J/cm2 of long‐wave ultraviolet radiation (UV‐A).

Photocontact sensitization was induced to 3,3′,4′,5‐tetrachlorosalicylanilide (TCSA); dibromosalicylanilide (DBS) but not to tribromosalicylanilide unless the latter was contaminated with DBS. Jadit and bithionol were weak photoallergens. The highest rate of sensitization was given by 6‐methylcoumarin, a widely used synthetic fragrance. Hexachlorophene and trichlorocarbanilide were negative.
Contact sensitization to benzoyl peroxide following topical treatment of chronic leg ulcers
Authors: Jensen Ove , Petersen Steen Hagen , Vesterager Lene
Published: April 2006

Sixteen patients with chronic leg ulcers were treated with 10% benzoyl peroxide gel for 6 weeks. At the end of the treatment, patch tests with 2 % benzoyl peroxide in petrolatum and 10 % in a gel showed that nine patients (56 %.| had become sensitized. This high sensitization rate is in good accord with the results obtained by experimental investigations using human maximization tests and repeated insult patch tests. A strong sensitizer such as benzoyl peroxide should not be used in the routine treatment of chronic leg ulcers, despite its good healing effect.
Within‐population variation in hybridisation and transgene transfer between wild Brassica rapa and Brassica napus in the UK
Authors: Pallett D.W. , Huang L. , Cooper J.I. , Wang H.
Published: April 2006

Several studies in Europe and North America have shown that cultivated Brassica napus will readily hybridise with wild Brassica rapa but at widely different frequencies. To understand the implications of this phenomenon with regard to transgene flow, we examined the rate at which cultivated B. napus cv. Westar containing a capsid (coat protein, CP)‐coding sequence from Turnip mosaic virus (Potyvirus) hybridised under glasshouse conditions with wild B. rapa from Culham, in Oxfordshire, UK. We found that the hybridisation rate, as judged using simple sequence repeat (SSR)‐PCR and primer oligonucleotides specific for either the C or the A genomes in progeny from individual crosses varied from 5% to 100%. In hybrids (F1 progeny), transgene transfer was always observed (inferred by SSR‐PCR) when hybrids were detected. Our observations revealed a hitherto unrecorded source of variability in transgene flow to wild UK B. rapa.
DETECTION OF VIBRIO ALGINOLYTICUS AND VIBRIO PARAHAEMOLYTICUS IN SHELLFISH SAMPLES USING COLLAGENASE‐TARGETED MULTIPLEX‐PCR
Authors: DI PINTO ANGELA , CICCARESE GIUSEPPINA , FONTANAROSA MARIA , TERIO VALENTINA , TANTILLO GIUSEPPINA
Published: April 2006

The increase of Vibrio infections especially associated with the consumption of contaminated seafood and fish underlines the necessity of an efficient monitoring system for Vibrio spp. supported by appropriate detection tools both in food products and in clinical samples. The aim of this study was the evaluation of the reliability of the collagenase‐targeted multiplex‐polymerase chain reaction (m‐PCR) for the detection of Vibrio alginolyticus, Vibrio cholerae and Vibrio parahaemolyticus in shellfish samples enriched in alkaline peptone water (APW). The coupling of a pre‐enrichment phase of the samples with the specificity of the PCR‐based assay was applied successfully to the detection of V. alginolyticus and V. parahaemolyticus, demonstrating that collagenase‐target m‐PCR may be used as a valid molecular target to discriminate the three Vibrio species.
X-ray Photoelectron Spectroscopy Studies of Oxidized and Reduced Ce0.8Zr0.2O2(111) Surfaces
Authors: Azad Samina , Engelhard Mark , Peden C.H.F. , Thevuthasan S.
Published: April 2006

We have studied the electronic structure of oxidized and reduced Ce0.8Zr0.2O2(111) using x-ray photoelectron spectroscopy (XPS). The 50 nm thick Ce0.8Zr0.2O2(111) film was grown on a YSZ(111) substrate using oxygen plasma assisted molecular beam epitaxy (OPA-MBE). This film has been characterized using in situ reflection high energy electron diffraction (RHEED) and ex situ x-ray diffraction (XRD), high energy resolution transmission electron spectroscopy (HRTEM) and Rutherford backscattering spectroscopy (RBS). The surface of the Ce0.8Zr0.2O2(111) film used in this study is found to be unreconstructed and exhibits the structure of bulk CeO2(111) where Zr atoms occupy the lattice sites of Ce in the fluorite structure of ceria. The extent of surface reduction as a result of vacuum annealing has been reported here in addition to the electronic structure of the defect-free Ce0.8Zr0.2O2(111) surface.
Leishmania donovaniRequires Functional Cdc42 and Rac1 To Prevent Phagosomal Maturation
Authors: Lerm M. , Holm Å. , Seiron Å. , Särndahl E. , Magnusson K.-E. , Rasmusson B.
Published: April 2006

Leishmania donovanipromastigotes survive inside macrophage phagosomes by inhibiting phagosomal maturation. The main surface glycoconjugate on promastigotes, lipophosphoglycan (LPG), is crucial for survival and mediates the formation of a protective shell of F-actin around the phagosome. Previous studies have demonstrated that this effect involves inhibition of protein kinase Cα. The present study shows that functional Cdc42 and Rac1 are required for the formation of F-actin aroundL. donovaniphagosomes. Moreover, we present data showing that phagosomes containing LPG-defectiveL. donovani, which is unable to induce F-actin accumulation, display both elevated levels of periphagosomal F-actin and impaired phagosomal maturation in macrophages with permanently active forms of Cdc42 and Rac1. We conclude thatL. donovaniengages Cdc42 and Rac1 to build up a protective coat of F-actin around its phagosome to prevent phagosomal maturation.
Signal Transduction Mechanism Involved inClostridium perfringensAlpha-Toxin-Induced Superoxide Anion Generation in Rabbit Neutrophils
Authors: Oda Masataka , Ikari Syusuke , Matsuno Takayuki , Morimune Yuka , Nagahama Masahiro , Sakurai Jun
Published: April 2006

Clostridium perfringensalpha-toxin induces the generation of superoxide anion (O2−) via production of 1,2-diacylglycerol (DG) in rabbit neutrophils. The mechanism of the generation, however, remains poorly understood. Here we report a novel mechanism for the toxin-induced production of O2−in rabbit neutrophils. Treatment of the cells with the toxin resulted in tyrosine phosphorylation of a protein of about 140 kDa. The protein reacted with anti-TrkA (nerve growth factor high-affinity receptor) antibody and bound nerve growth factor. Anti-TrkA antibody inhibited the production of O2−and binding of the toxin to the protein. The toxin induced phosphorylation of 3-phosphoinositide-dependent protein kinase 1 (PDK1). K252a, an inhibitor of TrkA receptor, and LY294002, an inhibitor of phosphatidylinositol 3-kinase (PI3K), reduced the toxin-induced production of O2−and phosphorylation of PDK1, but not the formation of DG. These inhibitors inhibited the toxin-induced phosphorylation of protein kinase C θ (PKCθ). U73122, a phospholipase C (PLC) inhibitor, and pertussis toxin inhibited the toxin-induced generation of O2−and formation of DG, but not the phosphorylation of PDK1. These observations show that the toxin independently induces production of DG through activation of endogenous PLC and phosphorylation of PDK1 via the TrkA receptor signaling pathway and that these events synergistically activate PKCθ in stimulating an increase in O2−. In addition, we show the participation of mitogen-activated protein kinase-associated signaling events via activation of PKCθ in the toxin-induced generation of O2−.
Deletion of theMycobacterium tuberculosisResuscitation-Promoting Factor Rv1009 Gene Results in Delayed Reactivation from Chronic Tuberculosis
Authors: Tufariello JoAnn M. , Mi Kaixia , Xu Jiayong , Manabe Yukari C. , Kesavan Anup K. , Drumm Joshua , Tanaka Kathryn , Jacobs William R. , Chan John
Published: April 2006

Approximately one-third of the human population is latently infected withMycobacterium tuberculosis, comprising a critical reservoir for disease reactivation. Despite the importance of latency in maintainingM. tuberculosisin the human population, little is known about the mycobacterial factors that regulate persistence and reactivation. Previous in vitro studies have implicated a family of five relatedM. tuberculosisproteins, called resuscitation promoting factors (Rpfs), in regulating mycobacterial growth. We studied the in vivo role ofM. tuberculosis rpfgenes in an established mouse model ofM. tuberculosispersistence and reactivation. After an aerosol infection with theM. tuberculosisErdman wild type (Erdman) or single-deletionrpfmutants to establish chronic infections in mice, reactivation was induced by administration of the nitric oxide (NO) synthase inhibitor aminoguanidine. Of the fiverpfdeletion mutants tested, one (ΔRv1009) exhibited a delayed reactivation phenotype, manifested by delayed postreactivation growth kinetics and prolonged median survival times among infected animals. Immunophenotypic analysis suggested differences in pulmonary B-cell responses between Erdman- and ΔRv1009-infected mice at advanced stages of reactivation. Analysis ofrpfgene expression in the lungs of Erdman-infected mice revealed that relative expression of four of the fiverpf-like genes was diminished at late times following reactivation, when bacterial numbers had increased substantially, suggesting thatrpfgene expression may be regulated in a growth phase-dependent manner. To our knowledge, ΔRv1009 is the firstM. tuberculosismutant to have a specific defect in reactivation without accompanying growth defects in vitro or during acute infection in vivo.
Role for RpoS but Not RelA ofLegionella pneumophilain Modulation of Phagosome Biogenesis and Adaptation to the Phagosomal Microenvironment
Authors: Abu-Zant Alaeddin , Asare Rexford , Graham James E. , Abu Kwaik Yousef
Published: April 2006

The induction of virulence traits byLegionella pneumophilaat the post-exponential phase has been proposed to be triggered by the stringent response mediated by RelA, which triggers RpoS. We show thatL. pneumophila rpoSbut notrelAis required for early intracellular survival and replication within human monocyte-derived macrophages andAcanthamoeba polyphaga. In addition,L. pneumophila rpoSbut notrelAis required for expression of the pore-forming activity. We provide evidence that RpoS plays a role in the modulation of phagosome biogenesis and in adaptation to the phagosomal microenvironment. Thus, there is no functional link between the stringent response and RpoS in the pathogenesis ofL. pneumophila.