bluuebunny/crossref_metadata_2025 huggingface dataset:
Phonological Progress During the First 2 Years of Stuttering
Authors: Paden Elaine Pagel , Ambrose Nicoline Grinager , Yairi Ehud
Published: April 2006

This report is the third in a series on phonological impairment in children who stutter, comparing its extent in those whose stuttering will be persistent with those in whom that disorder will disappear spontaneously. The first (E. P. Paden & E. Yairi, 1996) compared small groups of these children with normally fluent children of the same ages and sex. The second (E. P. Paden, E. Yairi, & N. G. Ambrose, 1999) compared the phonological abilities evidenced soon after onset of stuttering for 84 young children. In that study, the mean level of phonological skills of the 22 participants whose stuttering eventually persisted for at least 4 years was found to be significantly poorer than that of 62 others whose stuttering would disappear without fluency intervention before that time. In the present study, recorded performances of the same 84 children, made 1 and 2 years later, were similarly evaluated to determine how their phonological development progressed after the initial visit. Results of assessment at the 1-year visit showed that the mean difference between the two groups of children was no longer significant. The children whose stuttering would persist had improved more phonologically than had those who would recover from stuttering. At the 2-year visit, the mean percentage of phonological error for the two groups was identical. Furthermore, at this assessment, only 3 of the children in the Persistent group and 11 of those in the Recovered group had not essentially mastered all of the 10 basic patterns of phonology that were the focus of our evaluation. The findings concerning the longitudinal covariance of stuttering and phonological skills provide information that should be considered in any attempt to explain the relation between the two.
Prosodic Control in Severe Dysarthria
Authors: Patel Rupal
Published: April 2006

Speakers with severe dysarthria are known to have reduced range in prosody. Consistent control within that range, however, has largely been ignored. In earlier investigations speakers with severe dysarthria were able to control pitch and duration for sustained vowel production despite reduced flexibility of control (Patel, 1998). The present experiment examined whether 8 speakers with severe dysarthria due to cerebral palsy used prosodic parameters of pitch contour and syllable duration for phrase-level productions. Speakers with dysarthria (
N
=8) produced 3-syllable phrases as questions and statements. Naïve listeners (
N
=48) classifed dysarthric productions as either questions or statements. Listeners were able to distinguish questions from statements with accuracy levels ranging from 81% to 98 %. We were also interested in studying how dysarthric speakers marked the question-statement contrast. Prosodic features of pitch contour and syllable duration were systematically removed from the original recorded vocalizations to examine the salience of these features on listener classification. Removal of pitch contour cues dramatically reduced listener accuracy scores to almost chance performance. Listeners found pitch contour cues to be informationbearing cues in dysarthric vocalizations even though the range of frequency control in these speakers may be reduced. That speakers with dysarthria were able to exert sufficient control to signal the question-statement contrast has implications for diagnostic and intervention practices aimed to optimally exploit prosodic control for enhancing communication efficiency.
Temporal Integration of Sinusoidal Increments in the Absence of Absolute Energy Cues
Authors: Formby C. , Heinz M. G. , Aleksandrovsky I. V.
Published: April 2006

Classical temporal integration (TI) is often viewed as a frequency-dependent, energy-based detection process. Detection thresholds for brief sinusoidal increments in either a fixed-level or a random-level broadband pedestal are reported that refute this traditional perspective of TI. Instead, evidence is presented that indicates (a) detection of absolute energy is not necessary for the TI effect and (b) the frequency dependence of TI is consistent with variations across frequency in peripheral auditory tuning, rather than the integration process per se. When peripheral frequency selectivity is controlled, TI can be explained by a frequencyinvariant integration process over at least the frequency range from 500 to 4000 Hz. This process is characterized by threshold improvements of 8–9 dB per decade increase in duration for increment durations between 10 and 300 ms.
Acoustic and Perceptual Correlates of Stress in Nonwords Produced by Children With Suspected Developmental Apraxia of Speech and Children With Phonological Disorder
Authors: Munson Benjamin , Bjorum Elissa M. , Windsor Jennifer
Published: April 2006

Previous research (L. Shriberg, D. Aram, & J. Kwiatkowski, 1997b, 1997c) has suggested that accuracy in producing linguistic stress reliably distinguishes between children with suspected developmental apraxia of speech (sDAS) and children with phonological disorder (PD). The current investigation tested this hypothesis by examining acoustic correlates of stress in trochaic (strong-weak) and iambic (weak-strong) nonwords produced by 5 children in each of these 2 groups. Four measures relating to stress production were examined: vowel duration, fundamental frequency (f
0
) at vowel midpoint, timing of the f
0
peak relative to vowel onset, and intensity at vowel midpoint. In addition, perceptual judgments of accuracy of stress production were obtained. No group differences in the production of stress were found; however, listeners judged that the nonword repetitions of children with sDAS matched the target stress contour less often than did the repetitions of children with PD. Multiple regression analyses found that mean vowel duration, as well as the relative duration and relative f
0
of stressed and stressless syllables, predicted listeners’ judgments of stress, although these variables only accounted for a small proportion of variance (21.8%). Thus, children with sDAS were able to produce acoustic differences between stressed and stressless syllables, but these differences were not consistently perceptible to listeners.
Posterior Pharyngeal Wall Position in the Production of Speech
Authors: Magen Harriet S. , Kang A. Min , Tiede Mark K. , Whalen D. H.
Published: April 2006

The posterior pharyngeal wall has been assumed to be stationary during speech. The present study examines this assumption in order to assess whether midsagittal widths in the pharyngeal region can be inferred from measurements of the anterior pharyngeal wall. Midsagittal magnetic resonance images and X-ray images were examined to determine whether the posterior pharyngeal wall from the upper oropharynx to the upper laryngopharynx shows anterior movement that can be attributed to variables in speech: vowel quality in both English and Japanese; vowels versus consonants as classes of speech sounds; sustained versus dynamically produced speech; and isolated words versus sentences. Measurements were made of the distance between the anterior portion of the vertebral body and the pharyngeal wall. The first measurement was on a line traversing the junction between the dens and the body of the second cervical vertebra (C2). The next three measurements were on lines at the inferior borders of the bodies of C2, C3, and C4. The measurements showed very little movement of the posterior pharyngeal wall, none of it attributable to speech variables. Therefore, the position of the posterior pharyngeal wall in this region can be eliminated as a variable, and the anterior portion of the pharynx alone can be used to estimate vocal cavities.
Tri-Word Presentations With Phonemic Scoring for Practical High-Reliability Speech Recognition Assessment
Authors: Gelfand Stanley A.
Published: April 2006

Speech recognition test reliability is optimized with 450 test items, and the Computer Assisted Speech Recognition Assessment (CASRA) test is a practical approach for achieving this goal by combining 50 presentations of 3 consonantvowel nucleus-consonant (CNC) words each with phonemic scoring (S. A. Gelfand, 1998). However, optimized reliability might not be essential if reliability is as high as possible in light of practical constraints and what the clinician is trying to do with the results. The CASRA paradigm addresses these compromise goals with a reduced number of 3-word sets: 25 sets yield 25 (groups) x 3 (words) x 3 (phonemes) = 225 test items, 20 sets give 20 x 3 x 3 = 180 items, and 10 sets provide 10 x 3x 3= 90 items. This study addressed the empirical reliability of such an approach, and the extent to which results on shortened versions predict full-test scores. Test and retest scores were obtained for 10-, 20-, and 25-set versions of the CASRA for 144 participants with a wide range of hearing ability. For group data, first and second scores were highly correlated and not significantly different from each other for all 3 test sizes. Performance based on 20 and 25 sets accounted for roughly 97% of the variance of full (50-set) test scores, and scores based on 10 sets accounted for about 88% of the full-test variance. Individual test-retest reliability agreed with theoretical expectations based on 95% binomial confidence intervals. Cases outside the 95% confidence limits were 7.6% for 10 sets, and 3.5% for 20 and 25 sets with phoneme scoring, and 4.9% for 10 and 20 sets and 3.5% for 25 sets with word scoring. The shortened CASRA is a practical way to achieve improvements in reliability over traditional word tests. The 20-set version may approximate the strongest compromise when trying to shorten test size without appreciably reducing reliability for clinical purposes. However, the 10-set version is probably a more practical approach for routine use because it accounts for 88% of full-test variance, is more reliable than a traditional 75-word test, and does not appear to be subject to significant short-term learning effects.
DNA Microarray Gene Expression Analysis of a Vocal Fold Polyp and Granuloma
Authors: Thibeault Susan L. , Hirschi Scot D. , Gray Steven D.
Published: April 2006

Genome-wide transcriptional profiling has important applications in advancing knowledge of vocal fold biology. With the use of DNA microarray technology, analysis of global patterns of gene expression can reveal unexpected networks of coordinated regulation in the extracellular matrix of the lamina propria. Transcriptional gene expression patterns for 2 vocal fold pathologies—vocal fold polyp (VP;
N
= 1) and vocal fold granuloma (VG;
N
= 1) were analyzed by means of DNA microarray analysis for 4,632 human genes using another patient's true vocal fold (TVF;
N
= 1) as a control. Twenty-four and 29 genes for VG and VP, respectively, were established to be either over- or underexpressed compared to that of TVF. Five-way cluster analysis revealed broad patterns that suggest a potential degree of organization underlying gene expression in these tissues. For the 1 VG, genes involved represent inflammation and wound healing; for the 1 VP, involved genes demonstrate a tempered wound repair response and increased epithelial manifestations. These results successfully demonstrate the use of DNA microarray technology as a new approach for further investigations dissecting vocal fold disease. Further investigation is needed on larger sample sizes to establish transcriptional gene expression patterns for VP and VG.
Is Listener Comfort a Viable Construct in Stuttering Research?
Authors: O'Brian Sue , Packman Ann , Onslow Mark , Cream Angela , O'Brian Nigel , Bastock Kaely
Published: April 2006

This article reports the development of a tool for measuring how comfortable a person feels when communicating with someone who has undergone treatment for stuttering. The person rates the speaker on a 9-point Listener Comfort Scale (9 =
extremely comfortable
, 1 =
extremely uncomfortable
). In a preliminary investigation of the reliability and validity of the scale, 15 unsophisticated listeners rated video recordings of 10 adults before and after a prolonged-speech treatment for stuttering and of 10 matched controls. The results were compared with those of another 15 listeners who rated the same recordings with the widely used 9-point Speech Naturalness Scale (R. R. Martin, S. K. Haroldson, & K. A. Triden, 1984). Results showed that reliability of the Speech Naturalness Scale was superior to the Listener Comfort Scale, although users of both scales were able to distinguish between pretreatment speech, posttreatment speech, and the speech of controls. The results suggest that the Listener Comfort Scale captures information that is somewhat different than the information captured by the Speech Naturalness Scale. The authors concluded that the concept of listener comfort is a potentially useful additional way of investigating the social validity of behavioral treatments for stuttering.
Interarticulator Coordination in Dysarthria
Authors: Weismer Gary , Yunusova Yana , Westbury John R.
Published: April 2006

Articulatory discoordination is often said to be an important feature of the speech production disorder in dysarthria, but little experimental work has been done to identify and specify the coordination difficulties. The present study evaluated the coordination of labial and lingual gestures for /u/ production in persons with Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and in control participants. Both tongue backing/raising and reduction of the area enclosed by the lips can produce the characteristic low F2 of /u/. The timing of these articulatory gestures with respect to the acoustic target of a low F2 was inferred from X-ray microbeam data. Pellet motions of the tongue dorsum and lips revealed the timing of the lingual and labial gestures to be strongly linked together (synchronized), predictive of the temporal location of the lowest F2 within the vocalic nucleus, and scaled proportionately to the overall vowel duration in control participants. Somewhat surprisingly, essentially the same findings were obtained in the speakers with dysarthria. These relationships were noisier among the speakers with dysarthria, but the global synchronization patterns applied to all 3 groups. Further analyses revealed the synchronization to be less well defined and more variable across speakers with ALS, as compared to speakers with PD and the controls. Results are discussed relative to concepts of coordination in dysarthria.
Contributions of Semantic and Facial Information to Perception of Nonsibilant Fricatives
Authors: Jongman Allard , Wang Yue , Kim Brian H.
Published: April 2006

Most studies have been unable to identify reliable acoustic cues for the recognition of the English nonsibilant fricatives /f, v, θ, ð/. The present study was designed to test the extent to which the perception of these fricatives by normal-hearing adults is based on other sources of information, namely, linguistic context and visual information. In Experiment 1, target words beginning with /f/, /θ/, /s/, or /∫/ were preceded by either a semantically congruous or incongruous precursor sentence. Results showed an effect of linguistic context on the perception of the distinction between /f/ and /θ/ and on the acoustically more robust distinction between /s/ and /∫/. In Experiment 2, participants identified syllables consisting of the fricatives /f, v, θ, ð/ paired with the vowels /i, a, u/. Three conditions were contrasted: Stimuli were presented with (a) both auditory and visual information, (b) auditory information alone, or (c) visual information alone. When errors in terms of voicing were ignored in all 3 conditions, results indicated that perception of these fricatives is as good with visual information alone as with both auditory and visual information combined, and better than for auditory information alone. These findings suggest that accurate perception of nonsibilant fricatives derives from a combination of acoustic, linguistic, and visual information.
Input That Contradicts Young Children’s Strategy for Mapping Novel Words Affects Their Phonological and Semantic Interpretation of Other Novel Words
Authors: Jarvis Lorna Hernandez , Merriman William E. , Barnett Michelle , Hanba Jessica , Haitsma Kylee S. Van
Published: April 2006

Children tend to choose an entity they cannot already label, rather than one they can, as the likely referent of a novel noun. The effect of input that contradicts this strategy on the interpretation of other novel nouns was investigated. In pre- and posttests, 4-year-olds were asked to judge whether novel nouns referred to "name-similar" familiar objects or novel objects (e.g., whetherjapplereferred to an apple or a binder clip). During an intervening treatment phase, they were asked to pick the referents of novel nouns from pairs of familiar objects (Experiments 1 and 3) or were taught subordinate names for familiar objects (Experiment 2). Most resisted the lure of phonological similarity in the pretest but increased selection of name-similar familiar objects over novel ones in the posttest. In Experiment 3, which involved monosyllables that differed in initial phoneme from the familiar words, treatment produced this effect only when accompanied by a rhyme-sensitization procedure. Experiment 2 included two other age groups: 2-year-olds, who were less resistant to phonological similarity in the pretest and responded to the treatment like the 4-year-olds; and adults, who nearly always selected the novel objects in the pretest and posttest. For children, the impact of treatment was positively associated with ability to detect phonological similarity and negatively associated with vocabulary size.
The Effect of Talker- and Listener-Related Factors on Intelligibility for a Real-Word, Open-Set Perception Test
Authors: Markham Duncan , Hazan Valerie
Published: April 2006

The aims of this study were to evaluate whether talker intelligibility is consistent across listeners differing in age and gender and to investigate the process of attunement to talker characteristics in children and adults. Word intelligibility rates were obtained from 135 listeners (adults, 11–12-year-olds, and 7–8-year-olds) for 45 talkers from a homogeneous accent group. There were 2 test conditions, each containing multiple talkers. Both test conditions contained multiple talkers. In the single-word condition, key words were presented in isolation, whereas in the triplet condition, triplets of key words were preceded by a precursor sentence by the same talker. For identical word materials, word intelligibility at a signal-to-noise ratio of +6 dB varied significantly across talkers from 81.2% to 96.4%. Overall, younger listeners made significantly more errors than older children or adults, and women talkers were more intelligible than other classes of talkers. The relative intelligibility of the 45 talkers was highly consistent across listener groups, suggesting that talker intelligibility is primarily determined by talker-related factors rather than by the interrelation of talker- and listener-related factors. The presence of a precursor sentence providing indexical information did improve word intelligibility for the bottom quartile of listeners in each of the listener groups.
Measurement of Stuttering in Adults
Authors: O’Brian Sue , Packman Ann , Onslow Mark , O’Brian Nigel
Published: April 2006

This study investigated the comparative reliability of 2 stuttering measurement tools when used by experienced judges: percentage of syllables stuttered (%SS) and a 9-point severity scale (SEV). The study also investigated the degree to which scores on 1 tool predict scores on the other and the distributions of stuttering when measured by these tools. Twelve experienced judges watched 3-min videotapes of 90 stuttering and 10 nonstuttering participants. Half the judges rated %SS, and half made severity ratings. Results showed very high intrajudge and interjudge agreement for both measures. There was a strong linear correlation between %SS scores and SEV scores. Based on this finding, it seems that the 2 measures can be regarded as largely interchangeable. The exception to this, however, was in cases where there was either a small number of significant fixed postures (blocks and prolongations) or a large number of innocuous repeated movements (repetitions) in the speech sample. In such cases, it appears that %SS and SEV scores combined would be needed to provide a valid measure of stuttering. SEV scores were more normally distributed than %SS scores, which were clearly skewed. The advantages and limitations of the SEV scale are discussed.
Auditory Temporal Pattern Discrimination and Reading Ability
Authors: McAnally Ken I. , Castles Anne , Bannister Susan
Published: April 2006

The relation between reading ability and performance on an auditory temporal pattern discrimination task was investigated in children who were either good or delayed readers. The stimuli in the primary task consisted of sequences of tones, alternating between high and low frequencies. The threshold interstimulus interval (ISI) for discrimination of differences in the temporal properties of the sequences was measured. An ISI threshold was also measured in a control task that was identical to the primary task, except all tones in a control sequence had the same frequency. Delayed readers and good readers were equally able to discriminate the timing of the sequences at short ISIs, for both the primary and control tasks. Furthermore, the ISI thresholds were not correlated with the ability to read either irregular words or nonwords. These results suggest that reading ability is not related to the ability to track large and rapid frequency changes in auditory temporal patterns.
Measures of Working Memory, Sequence Learning, and Speech Recognition in the Elderly
Authors: Humes Larry E. , Floyd Shari S.
Published: April 2006

This study describes the measurement of 2 cognitive functions, working-memory capacity and sequence learning, in 2 groups of listeners: young adults with normal hearing and elderly adults with impaired hearing. The measurement of these 2 cognitive abilities with a unique, nonverbal technique capable of auditory, visual, and auditory-visual stimulation, patterned after the Simon memory game, is described. The use of simple, easily understood items in the test sequences enabled the measurement of these cognitive abilities in older listeners with no apparent impact of age-related hearing loss on the cognitive measures. Age-related cognitive deficits were observed for all 3 modes of stimulation and in both working-memory capacity and sequence-learning ability. The age-related deficits appeared to be greatest, however, for the sequence-learning task. Although it was hypothesized that there might be an association between an individual's performance on these cognitive tasks and his or her performance on various measures of speech recognition, such an association generally was not observed.
Effect of Rate Reduction and Increased Loudness on Acoustic Measures of Anticipatory Coarticulation in Multiple Sclerosis and Parkinson's Disease
Authors: Tjaden Kris , Wilding Gregory E.
Published: April 2006

The present study compared patterns of anticipatory coarticulation for utterances produced in habitual, loud, and slow conditions by 17 individuals with multiple sclerosis (MS), 12 individuals with Parkinson's disease (PD), and 15 healthy controls. Coarticulation was inferred from vowel F2 frequencies and consonant first-moment coefficients. Rate-related changes in coarticulation differed depending on the particular phonetic events in an utterance. In some instances, the slow condition was associated with stronger anticipatory effects, but in other instances the slow condition was associated with weaker anticipatory effects, relative to other speaking conditions. In contrast, coarticulatory patterns for the loud and habitual conditions typically did not differ. Coarticulatory patterns also tended to be similar among speaker groups within each condition. Finally, when acoustic measures of coarticulation differed among speaking conditions, the direction and magnitude of the effect generally were similar for healthy controls, speakers with MS, and speakers with PD. These results are consistent with studies suggesting mostly preserved patterns of coarticulation for speakers with mild to moderate dysarthria, as well as research indicating only subtle coordination deficits for individuals with dysarthria. The finding that increased loudness had a negligible effect on coarticulation also appears to be at odds with the suggestion that increased loudness stimulates orofacial coordination for speakers with dysarthria, although studies including speakers exhibiting coordination impairments at habitual speaking rates would provide a stronger test of this suggestion. Lastly, the fact that speaking condition similarly affected acoustic measures of anticipatory coarticulation for all speaker groups suggests the feasibility of applying theories and models of speech production for neurologically normal talkers to the study of dysarthria.
An Application of Rasch Analysis to the Measurement of Communicative Functioning
Authors: Doyle Patrick J. , Hula William D. , McNeil Malcolm R. , Mikolic Joseph M. , Matthews Christine
Published: April 2006

Purpose:
The purposes of this investigation were to examine the construct dimensionality and range of ability effectively measured by 28 assessment items obtained from 3 different patient-reported scales of communicative functioning, and to provide a demonstration of how the Rasch approach to measurement may contribute to the definition of latent constructs and the development of instruments to measure them.

Method:
Item responses obtained from 421 stroke survivors with and without communication disorders were examined using the Rasch partial credit model. The dimensionality of the item pool was evaluated by (a) examining correlations of Rasch person ability scores obtained separately from each of the 3 scales, (b) iteratively excluding items exceeding mean square model fit criteria, and (c) using principal-components analysis of Rasch model residuals. The range of ability effectively measured by the item pool was examined by comparing item difficulty and category threshold calibrations to the distribution of person ability scores and by plotting the modeled standard error of person ability estimates as a function of person ability level.

Results:
The results indicate that most assessment items fit a unidimensional measurement model, with the notable exception of items relating to the use of written communication. The results also suggest that the range of ability that could be reliably measured by the current item pool was restricted relative to the range of ability observed in the patient sample.

Conclusions:
It is concluded that (a) a mature understanding of communicative functioning as a measurement construct will require further research, (b) patients with stroke-related communication disorders will be better served by the development of instruments measuring a wider range of communicative functioning ability, and (c) the theoretical and methodological tools provided by the Rasch family of measurement models may be productively applied to these efforts.
Improving the efficiency of polymer light-emitting electrochemical cells by controlled doping relaxation
Authors: Zhang Yanguang , Hu Yufeng , Gao Jun
Published: April 2006

We show that a frozen p-n junction in a polymer light-emitting electrochemical cell can relax into a p-i-n junction when heated briefly to above the glass transition temperature of the polymer electrolyte used. This results in a less doped “quasi-intrinsic” emission zone with reduced photoluminescence quenching due to electrochemical doping. A 408%–2678% increase in electroluminescence efficiency has been demonstrated by controlled doping relaxation. The formation of a p-i-n junction has been confirmed by spatially resolved imaging of the doping profile in a planar device structure.
Grain-boundary-controlled current transport in copper phthalocyanine
Authors: Mahapatro Ajit Kumar , Sarkar Niladri , Ghosh Subhasis
Published: April 2006

Anomalous temperature dependence of resistivity at low temperature is observed in copper-phthallocyanine thin film. A model based on grain-boundary-controlled transport has been developed for the explanation of the observed anomaly. The prediction is based on the assumption that the thin film beyond a certain thickness is mainly polycrystalline, consisting of grains. The transport is expected to be limited by potential barriers at grain boundaries.
Caspases leave the beaten track: caspase-mediated activation of NF-κB
Authors: Lamkanfi Mohamed , Declercq Wim , Vanden Berghe Tom , Vandenabeele Peter
Published: April 2006

The proteolytic activity of the cysteinyl aspartate–specific proteases, named caspases, mainly connotes their central role in apoptosis and inflammation. In this review we report on recent data on the role of caspases in the activation of nuclear factor κB (NF-κB), a transcription factor that fulfils a central role in innate and adaptive immunity, in cellular stress responses and in the induction of anti-apoptotic factors. Two different mechanisms by which caspases activate the NF-κB pathway are discussed.
Does the implementation of a clinical information system decrease the time intensive care nurses spend on documentation of care?
Authors: Saarinen K. , Aho M.
Published: April 2006

Background:  The number of intensive care units (ICU) using a clinical information system (CIS) is increasing. It is believed that replacing manual charting with an automatic documentation system allocates nurses more time for patient care. The objective of this study was to measure changes in nurses' working time utilization after the implementation of a CIS in a polyvalent ICU of a large Finnish central hospital.

Methods:  An activity analysis‐based comparison of the ICU nurses' working time utilization before and after the implementation of a CIS.

Results:  After the implementation of a CIS the total time the nurses spent on documentation of nursing care increased by 3.6% (NS), 15 min per shift of 8 h per nurse. The total time they spent on patient care increased by 5.5% (P < 0.05), 21 min. Intensive care nursing activities increased by 3.7% (P < 0.05), 14 min. The length of the nurses' ICU experience had some effect on these figures. The demand for nurse labor remained constant.

Conclusions:  After the implementation of a CIS, an increase in the time nurses spent on documentation of care was detected, which suggests a need for further development of the system. As all the measured time changes were relatively small, any plans to reduce the ICU staff number with the aid of computers were not justified.
Scaling‐up from leaf to canopy‐aggregate properties in sclerophyll shrub species
Authors: READ CASSIA , WRIGHT IAN J. , WESTOBY MARK
Published: April 2006

Abstract:  Plant species vary widely in their average leaf lifespan (LL) and specific leaf area (SLA, leaf area per dry mass). The negative LL–SLA relationship commonly seen among species represents an important evolutionary trade‐off, with higher SLA indicating greater potential for fast growth (higher rate of return on a given investment), but longer LL indicating a longer duration of the revenue stream from that investment. We investigated how these leaf‐economic traits related to aggregate properties of the plant crown. Across 14 Australian sclerophyll shrub species, those with long LL accumulated more leaf mass and leaf area per unit ground area. Light attenuation through their canopies was more severe. Leaf accumulation and light attenuation were more weakly related to SLA than to LL. The greater accumulation of foliage in species with longer LL and lower SLA may counterbalance their generally lower photosynthetic rates and light‐capture areas per gram of leaf.
Trauma response to the Asian tsunami: Krabi Hospital, Southern Thailand
Authors: Johnson Luke J , Travis Angela R
Published: April 2006

The date 26 December 2004 saw a massive tidal wave propagated from a 9.0 Richter scale suboceanic earthquake off the coast of Sumatra in South‐East Asia. It swept across the Indian Ocean over a matter of hours leaving destruction in its wake. In Southern Thailand, Krabi Hospital, that province's major tertiary health centre, received the majority of the region's tsunami victims. Well‐rehearsed contingency plans were in place to cope with 10, 20 and 40 trauma victims in the case of an extreme event. By the end of 26 December some 500 injured people had been treated at Krabi Hospital: well in excess of the ‘worst case scenario’ planning. Over the following days a total of 1357 tsunami victims were treated. Over the course of the day victims were able to move through the hospitals’ system and gain appropriate treatment. This was achieved through the almost superhuman dedication of the hospitals’ well‐trained nursing and medical staff. In addition to this were large numbers of both Thai and foreign volunteers, who aided people with basic necessities such as providing them with food, water and clothing as well as simple human comfort, some also acting as translators for the health‐care workers and the masses of injured and displaced people. Makeshift wards were constructed in halls and little used areas of the hospital, using army style stretchers to accommodate the wounded. Even though the disaster contingency plans at Krabi Hospital were utterly overrun, the fact that well‐thought out and practised strategies were in place saved incalculable lives. The message is clear: practised responses to mass trauma situations will save lives and allows health‐care teams to coordinate well in the face of overwhelming odds without panic. All centres should routinely practise disaster response through scenario‐based training.
Fuchs-Kliewer Phonon Spectrum of Co3O4(110) by High Resolution Electron Energy Loss Spectroscopy
Authors: Marsh E. M. , Petitto S. C. , Langell M. A.
Published: April 2006

High resolution electron energy loss spectroscopy (HREELS) was used to obtain the Fuchs-Kliewer phonon spectrum of Co3O4(110). Auger electron spectroscopy (AES), x-ray photoelectron spectroscopy (XPS), and low energy electron diffraction (LEED) provided information on sample integrity. The AES, XPS, and LEED specta confirm the cleanliness, composition, and the order of the Co3O4(110) surface. The HREEL spectra show the Fuchs-Kliewer phonon structure with peaks appearing at 26.8, 47.5, 71.1, and 84.7 meV (216, 383, 573, and 683 cm−1), which correspond to the four fundamental phonons. Multiple losses of the fundamental phonons are also present in the spectra.
Potassium Manganate by XPS
Authors: Oku Masaoki , Shishido Toetsu , Kohiki Shigemi
Published: April 2006

Potassium manganate, K2MnO4, has an electronic structure of d1. As it has one unpaired electron, it has exchange interaction between the core and valence electrons in the photoemission process. It is an interesting question whether manganese compounds of high oxidation number and strong covalent bonding exhibit satellite peaks in XPS spectra, or not. This submission provides information that may be useful for the discussion of the photoemission process. In this study, XPS core- and valence-band level spectra including the energy loss parts were taken for the in situ fractured surfaces of K2MnO4 crystals. Crystals grown from an aqueous solution and stocked in KOH solution were used because the sample is moisture sensitive.
Nanocrystalline Lanthanum Oxyfluoride Thin Films by XPS
Authors: Barreca Davide , Gasparotto Alberto , Maragno Cinzia , Tondello Eugenio
Published: April 2006

Nanocrystalline lanthanum oxyfluoride thin films were synthesized by chemical vapor deposition (CVD) using La(hfa)3⋅diglyme (hfa=1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; diglyme=bis(2-metoxyethyl)ether) as precursor compound. The coatings were deposited on Si(100) and commercial silica slides in nitrogen+wet oxygen atmospheres, at temperatures between 200 and 500 °C, with particular attention to the structural and compositional evolution as a function of the synthesis conditions and growth surface. The obtained samples were characterized by glancing-incidence x-ray diffraction (GIXRD), secondary ion mass spectrometry (SIMS), x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), for a detailed determination of their microstructure, chemical composition, and surface morphology. This work is dedicated to the XPS characterization of a representative LaOF thin film deposited on Si(100) at 500 °C. Besides the wide scan spectrum, detailed spectra for the La 3d, F 1s, O 1s, and C 1s regions and related data are presented and discussed. Both the F/La atomic ratio and La 3d peak shape and position point to the formation of stoichiometric LaOF thin films. Moreover, carbon contamination was merely limited to the outermost sample layers.
Murine Malaria Infection Induces Fetal Loss Associated with Accumulation ofPlasmodium chabaudiAS-Infected Erythrocytes in the Placenta
Authors: Poovassery Jayakumar , Moore Julie M.
Published: April 2006

Malarial infection in nonimmune women is a risk factor for pregnancy loss, but the role that maternal antimalarial immune responses play in fetal compromise is not clear. We conducted longitudinal and serial sacrifice studies to examine the pathogenesis of malaria during pregnancy using thePlasmodium chabaudiAS/C57BL/6 mouse model. Peak parasitemia following inoculation with 1,000 parasite-infected murine erythrocytes and survival were similar in infected pregnant and nonpregnant mice, although development of parasitemia and anemia was slightly accelerated in pregnant mice. Importantly, pregnant mice failed to maintain viable pregnancies, most aborting before day 12 of gestation. At abortion, maternal placental blood parasitemia was statistically significantly higher than peripheral parasitemia. Infected mice had similar increases in spleen size and cellularity which were statistically significantly higher than in uninfected mice. In contrast, splenocyte proliferation in response to mitogenic stimulation around peak parasitemia was statistically significantly reduced in both groups of infected mice compared to uninfected, nonpregnant mice, suggesting that lymphoproliferation is not a good indicator of the antimalarial immune responses in pregnant or nonpregnant animals. This study suggests that while pregnant and nonpregnant C57BL/6 mice are equally capable of mounting an effective immune response to and survivingP. chabaudiAS infection, pregnant mice cannot produce viable pups. Fetal loss appears to be associated with placental accumulation of infected erythrocytes. Further study is required to determine to what extent maternal antimalarial immune responses, anemia, and placental accumulation of parasites contribute to compromised pregnancy in this model.
Multiple Chromosomal Loci for the
babA
Gene in
Helicobacter pylori
Authors: Hennig Ewa E. , Allen Johnna M. , Cover Timothy L.
Published: April 2006

Helicobacter pylori babA
encodes an outer membrane protein that binds to fucosylated Lewis b blood group antigen. We analyzed a panel of 35
H. pylori
strains and identified three possible chromosomal loci for
babA
. There was a significant association between the presence of
babA
and the presence of
cagA
(
P
= 0.0001). Phylogenetic analysis of
babA
alleles revealed two divergent families of signal sequences. Among 17 strains in which an intact in-frame
babA
allele was identified, 10 expressed a detectable BabA protein. Expression of a BabA protein and the Lewis b-binding phenotype were not dependent on the chromosomal locus of
babA
. These data indicate that there is marked heterogeneity among
H. pylori
strains in
babA
genetic content and BabA expression.
Pathogenomic Sequence Analysis of
Bacillus cereus
and
Bacillus thuringiensis
Isolates Closely Related to
Bacillus anthracis
Authors: Han Cliff S. , Xie Gary , Challacombe Jean F. , Altherr Michael R. , Bhotika Smriti S. , Bruce David , Campbell Connie S. , Campbell Mary L. , Chen Jin , Chertkov Olga , Cleland Cathy , Dimitrijevic Mira , Doggett Norman A. , Fawcett John J. , Glavina Tijana , Goodwin Lynne A. , Hill Karen K. , Hitchcock Penny , Jackson Paul J. , Keim Paul , Kewalramani Avinash Ramesh , Longmire Jon , Lucas Susan , Malfatti Stephanie , McMurry Kim , Meincke Linda J. , Misra Monica , Moseman Bernice L. , Mundt Mark , Munk A. Christine , Okinaka Richard T. , Parson-Quintana B. , Reilly Lee Philip , Richardson Paul , Robinson Donna L. , Rubin Eddy , Saunders Elizabeth , Tapia Roxanne , Tesmer Judith G. , Thayer Nina , Thompson Linda S. , Tice Hope , Ticknor Lawrence O. , Wills Patti L. , Brettin Thomas S. , Gilna Paul
Published: April 2006

Bacillus anthracis
,
Bacillus cereus
, and
Bacillus thuringiensis
are closely related gram-positive, spore-forming bacteria of the
B. cereus
sensu lato group. While independently derived strains of
B. anthracis
reveal conspicuous sequence homogeneity, environmental isolates of
B. cereus
and
B. thuringiensis
exhibit extensive genetic diversity. Here we report the sequencing and comparative analysis of the genomes of two members of the
B. cereus
group,
B. thuringiensis
97-27 subsp.
konkukian
serotype H34, isolated from a necrotic human wound, and
B. cereus
E33L, which was isolated from a swab of a zebra carcass in Namibia. These two strains, when analyzed by amplified fragment length polymorphism within a collection of over 300 of
B. cereus
,
B. thuringiensis
, and
B. anthracis
isolates, appear closely related to
B. anthracis
. The
B. cereus
E33L isolate appears to be the nearest relative to
B. anthracis
identified thus far. Whole-genome sequencing of
B. thuringiensis
97-27and
B. cereus
E33L was undertaken to identify shared and unique genes among these isolates in comparison to the genomes of pathogenic strains
B. anthracis
Ames and
B. cereus
G9241 and nonpathogenic strains
B. cereus
ATCC 10987 and
B. cereus
ATCC 14579. Comparison of these genomes revealed differences in terms of virulence, metabolic competence, structural components, and regulatory mechanisms.
Role of Secondary Attachment Sites in Changing the Specificity of Site-Specific Recombination
Authors: Rutkai Edit , György Andrea , Dorgai László , Weisberg Robert A.
Published: April 2006

We previously proposed that lambdoid phages change their insertion specificity by adapting their integrases to sequences found in secondary attachment sites. To test this model, we quantified recombination between partners that carried sequences from secondary attachment sites catalyzed by wild-type and by mutant integrases with altered specificities. The results are consistent with the model, and indicate differential core site usage in excision and integration.
Evidence from mosquitoes suggests that cyclic gas exchange and discontinuous gas exchange are two manifestations of a single respiratory pattern
Authors: Gray Emilie M. , Bradley Timothy J.
Published: April 2006

In this paper we demonstrate that the apparent pattern of gas exchange in insects, as observed using flow-through respirometry, is strongly affected by the rate of flow of air through the system. This is true not only because of the time constant of the respiratory chamber in which the insect resides, but also due to the effect of flow rate on the residence time of air as it passes through the detection chamber in the gas analyzer. It is demonstrated that insects respiring with a discontinuous gas exchange pattern can appear to be using a cyclic respiratory pattern. The effects of flow rate on the respiratory pattern discerned are illustrated using the mosquito Culiseta inornata. It is demonstrated that these mosquitoes respire discontinuously. They are among the smallest insects to date in which the discontinuous gas exchange cycle has been observed.
Spectral selectivity during phonotaxis: a comparative study in Neoconocephalus (Orthoptera: Tettigoniidae)
Authors: Deily Joshua A. , Schul Johannes
Published: April 2006

The calls of male Neoconocephalus have most energy concentrated in a relatively narrow low-frequency band. In N. robustus this low-frequency band is centered around 7 kHz, whereas calls of N. nebrascensis and N. bivocatus have center frequencies close to 10 kHz. The importance of the position of the low-frequency band for female phonotaxis in these three species was determined using a walking compensator. Female N. robustus showed significant phonotaxis towards call frequencies from 5 to 10 kHz, and spectral selectivity towards higher frequencies did not change with stimulus amplitude. Significant responses in N. nebrascensis and N. bivocatus occurred at significantly higher frequency ranges than in N. robustus. In these species,spectral selectivity changed with stimulus amplitude; at 68 dB sound pressure level (SPL), upper cut-off frequency was significantly lower than at 80 dB SPL in both species. Adding a higher harmonic to the conspecific carrier frequency had a strong inhibitory effect on phonotaxis in N. robustus: at higher relative amplitudes of the harmonic, phonotaxis was completely suppressed. Adding a higher harmonic to the conspecific carrier frequency had a much weaker but significant inhibitory effect in N. nebrascensisand little, if any, effect in N. bivocatus. The processing of song spectrum in the sensory system is discussed with regard to the differences in spectral selectivity among the three species. The sharp spectral selectivity of N. robustus is interpreted as an adaptation for species isolation.
Halphen conditions and postulation of nodes
Authors: Chiantini L. , Chiarli N. , Greco S.
Published: April 2006

We give sharp lower bounds for the postulation of the nodes of a general plane projection of a smooth connected curve C ⊆ ℙ
r
and we study the relationships with the geometry of the embedding. Strict connections with Castelnuovo’s theory and Halphen’s theory are shown.