bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wind model for low frequency power fluctuations in offshore wind farms
Authors: Vigueras‐Rodríguez A. , Sørensen P. , Cutululis N. A. , Viedma A. , Donovan M. H. 
Published: December 2009

AbstractThis paper investigates the correlation between the frequency components of the wind speed Power Spectral Density. The results extend an already existing power fluctuation model that can simulate power fluctuations of wind power on areas up to several kilometers and for time scales up to a couple of hours, taking into account the spectral correlation between different wind turbines. The modelling is supported by measurements from two large wind farms, namely Nysted and Horns Rev. Measurements from individual wind turbines and meteorological masts are used. Finally, the models are integrated into an aggregated model which is used for estimating some electrical parameters as power ramps and reserves requirements, showing a quite good agreement between simulations and measurement. The comparison with measurements generally show that the inclusion of the correlation between low frequency components is an improvement, but the effect is relatively small. The effect of including the low frequency components in the model is much more significant. Therefore, that aggregated model is useful in the power system planning and operation, e.g. regarding load following and regulation. Copyright © 2009 John Wiley & Sons, Ltd.
Brownian bridge
Authors: Chow Winston C. 
Published: December 2009

AbstractA Brownian bridge is a stochastic process derived from standard Brownian motion by requiring an extra constraint. This gives Brownian bridges unique mathematical properties, fascinating, itself, and useful in statistical and mathematical modeling. Here, we define a Brownian bridge and explain some of its unique mathematical properties. These properties make it useful as a mathematical model for real‐world phenomena and as a tool for statistical analysis. We then give some examples of applications. We will see many mathematical ideas that touch Brownian bridges, such as differential equations, linear spaces, topology, metric spaces of functions, measure theory, stochastic integrals, estimation, and hypothesis testing. Copyright © 2009 Wiley Periodicals, Inc.This article is categorized under:

Statistical Models > Time Series Models
Data: Types and Structure > Time Series, Stochastic Processes, and Functional Data
Bayesian networks
Authors: Jensen Finn V. 
Published: December 2009

AbstractBayesian networks are defined, and the chain rule for Bayesian networks is stated. Outlines of algorithms provided: inference in Bayesian networks, sensitivity analysis, EM for parameter learning, and learning structure. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:Statistical and Graphical Methods of Data Analysis > Bayesian Methods and Theory
Intraoperative Assessment of Sentinel Node Using Imprint Cytology
Authors: Clarke Dayalan , Leung Edmund , Chachlani Naresh , Rowlands David , Simon Jayanthi , Hero Isabel , England David 
Published: December 2009

AbstractBackgroundSentinel lymph node (SLN) biopsy has replaced axillary sampling as the axillary staging procedure of choice in patients with breast cancer. Accurate intraoperative evaluation of the SLN would allow axillary lymph node clearance to be performed during the initial operation when the SLN is positive for metastatic disease. The aim of the present study was to assess the accuracy of intraoperative imprint cytology (IC) of the SLN in two different institutions in the United Kingdom.MethodsAll breast cancer patients who underwent a SLN biopsy using a standard protocol in two hospital breast units were included. The SLN was sent fresh to the pathology laboratory, where it was immediately processed and examined by a cytopathologist using IC. The intraoperative IC results were compared with the final histopathological results. No therapeutic decisions were made based on the results of IC in this study.ResultsA total of 166 patients were included, with 47 positive and 119 negative cases on final histology. Of the 47 patients who were positive on final histology, there were 29 positive and 18 negative cases on IC (sensitivity = 61.7%). All 119 patients who were negative on final histology were negative on IC (specificity, 100%). The negative and positive predictive value of the final histology was 86.9% and 100%, respectively. The accuracy of IC was 89.2%.ConclusionsThe results from these two breast units are comparable with findings reported in the published literature, confirming that IC can be used to assess SLN biopsy intraoperatively. No unnecessary axillary node clearance would have been carried out based on the results of IC.
Increased Serum Levels of C‐Reactive Protein Precede Anastomotic Leakage in Colorectal Surgery
Authors: Woeste Guido , Müller Christine , Bechstein Wolf O. , Wullstein Christoph 
Published: December 2009

AbstractBackgroundAnastomotic leakage (AL) is a severe complication following colorectal surgery. C‐reactive protein (CRP) is considered to be an indicator of postoperative complications.Materials and methodsBetween August 2002 and August 2005 342 colorectal resections with primary anastomosis were performed at the Department of General and Vascular Surgery. Johann Wolfgang Goethe‐University Frankfurt. For this retrospective study serum CRP was measured daily until postoperative day 7, and in cases of AL it was excluded from statistical analysis beginning with the day on which the AL was diagnosed.ResultsTwenty‐six of 342 (7.6%) patients developed AL at a mean of 8.7 days postoperatively. The in‐hospital mortality was 3.5% for all patients and was significantly higher in the AL group (11.5 versus 2.8%). The CRP level in the two groups showed a peak on day 2.5 and day 2.2, respectively. In case of postoperative AL the CRP level did not show a marked decline during the next few days. Compared to the cases where AL did not develop, there was a significantly higher increase in CRP from the preoperative level to the levels measured on postoperative day 3, 5, 6 and 7. Higher CRP levels were observed in patients experiencing pneumonia or urinary tract infection, but the decrease of CRP values was not as slow as in cases of AL.ConclusionsThis study shows serum CRP level to be a relevant marker in detecting postoperative complications in colorectal surgery. Prolonged elevation and a missing decline in CRP level precede the occurrence of AL.
B‐Lynch suture, intrauterine balloon, and endouterine hemostatic suture for the management of postpartum hemorrhage due to placenta previa accreta
Authors: Arduini Maurizio , Epicoco Giorgio , Clerici Graziano , Bottaccioli Elvira , Arena Saverio , Affronti Giuseppe 
Published: December 2009

AbstractObjectiveTo report our experience with a new conservative management approach to treat postpartum hemorrhage (PPH) due to placenta previa accreta.MethodsA retrospective study of 9 patients with placenta previa accreta who underwent a conservative management protocol. The protocol consists of preventive radiological catheterization of the descending aorta, cesarean delivery, use of Affronti endouterine square hemostatic sutures, and placement of an intrauterine Bakri balloon in conjunction with B‐Lynch suture. In the event of failure of the protocol, subsequent management employs ligation and/or reversible embolization of the uterine arteries followed by hysterectomy if unsuccessful.ResultsConservative management of PPH was successful in all 9 patients evaluated and avoided the need for ligation and/or reversible embolization of the uterine arteries.ConclusionManagement of PPH is dictated by several considerations including hemodynamic status and desire to preserve fertility. The initial results of this conservative protocol for treatment of PPH in high‐risk patients with placenta previa accreta are encouraging.
Risk of heart failure relapse in subsequent pregnancy among peripartum cardiomyopathy mothers
Authors: Fett James D. , Fristoe Karie L. , Welsh Serena N. 
Published: December 2009

AbstractObjectiveTo quantify the level of risk for heart failure relapse in a subsequent pregnancy in women who have had peripartum cardiomyopathy (PPCM), and to test the hypothesis that meeting additional criteria may help lower the risk.MethodsProspectively‐identified PPCM patients volunteering between 2003 and 2009 were identified from the PPCM Registry of Hôpital Albert Schweitzer, Deschapelles, Haiti, and an internet support group. Data were assessed for full adherence to monitoring and diagnostic criteria, clinical data, statistical analysis, and reporting.ResultsOf 61 post‐PPCM pregnancies identified, there were 18 relapses (29.5%) of heart failure. Of 26 pregnancies with a left ventricular ejection fraction (LVEF) of less than 0.55 prior to the pregnancy, relapse occurred in 12 (46.2%) pregnancies. Of 35 pregnancies with an LVEF of 0.55 or greater prior to the pregnancy, relapse occurred in 6 (17.1%) (P < 0.01). No relapses occurred in 9 women who also demonstrated adequate contractile reserve.ConclusionThe most important criterion associated with reduced risk for heart failure relapse in a post‐PPCM pregnancy is recovery defined by an LVEF 0.55 or greater before the subsequent pregnancy. Exercise stress echocardiography showing adequate contractile reserve may help to identify women at an even lower risk of relapse.
Socioeconomic context of land use and land cover change in Mexican biosphere reserves
Authors: FIGUEROA FERNANDA , SÁNCHEZ-CORDERO VÍCTOR , MEAVE JORGE A. , TREJO IRMA 
Published: December 2009

SUMMARYLand use/land cover change (LULC) is a major threat to natural protected areas worldwide. This paper explores the relationships between four estimated LULC parameters for 17 Mexican biosphere reserves (BRs) for 1993–2002 on a GIS platform, and ten socioeconomic factors obtained from census data. These relationships were tested through linear correlations and multivariate analysis. BRs showed lower human demographic pressure, but higher population dispersion, social marginality, percentage of rain-fed agriculture area, and dependence upon agriculture and cattle compared to nationwide values. BRs also varied in their indigenous population, and showed cattle overpopulation, and low immigration and road density. Socioeconomic factors explained 87% of LULC variation. High population and road density, cattle overpopulation and low percentage indigenous population were related to percentage of transformed area (2002). Conversely, small population and road density, large proportion of indigenous population and high dependency on agriculture and cattle, were related to the rate of change in transformed area (1993–2002). High human population growth and urban concentration occurred when BRs suffered higher LULC than their corresponding ecoregions. Including socioeconomic conditions prevailing in BRs and their influence on LULC in reserve management and rural development planning will improve strategies for the confluence of conservation and development goals.
Antarctic climate change and the environment
Authors: Convey P. , Bindschadler R. , di Prisco G. , Fahrbach E. , Gutt J. , Hodgson D.A. , Mayewski P.A. , Summerhayes C.P. , Turner J. ,   the ACCE Consortium
Published: December 2009

AbstractThe Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (∼the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential Southern Hemisphere companion to the Arctic Climate Impact Assessment.
Measuring Tinnitus Loudness Using Constrained Psychophysical Scaling
Authors: Ward Lawrence M. , Baumann Michael 
Published: December 2009

PurposeWe measured tinnitus loudness using a new method of psychophysical scaling with the aim of introducing a potentially useful new procedure to the literature.MethodFourteen adults reporting tinnitus were trained to use a standardized loudness scale, and then they used that response scale to assess loudness of nonstandard stimuli and of their tinnitus. We also measured tinnitus loudness and pitch using a computer-based matching procedure, and we measured the impact of tinnitus on daily living using the Tinnitus Handicap Inventory (THI; C. W. Newman, G. P. Jacobson, & J. B. Spitzer, 1996) for those 14 individuals and an additional 2 participants.Results and ConclusionsOur 14 trained participants judged loudness similarly to normal hearing participants for pure tones at normal hearing, nontinnitus frequencies—implying that their judgments of tinnitus loudness were valid. Constrained scaling of tinnitus loudness yielded measurements that were substantially greater than the sensation level of sounds matched to tinnitus loudness. Our total of 16 participants fell into 2 groups on the basis of hearing loss, extent of abnormal loudness growth at the tinnitus frequency, and several aspects of tinnitus experience. Finally, as previously found, there was little correlation between tinnitus loudness, no matter how measured, and the impact of tinnitus on daily life as measured by the THI.
Pediatricians’ Knowledge of, Experience With, and Comfort Levels for Cochlear Implants in Children
Authors: Mathews Melody R. , Johnson Carole E. , Danhauer Jeffrey L. 
Published: December 2009

Purpose
Pediatricians are vital to early hearing detection and intervention programs (EHDIPs) and influence families’ decisions and compliance with recommendations for their children having hearing loss. Pediatricians need current, accurate knowledge about diagnostics and treatments including cochlear implants (CIs). This study assessed pediatricians’ knowledge about, experience with, and comfort levels for CIs in children.

Method
Questionnaires were mailed to a total of 220 pediatricians in 9 cities in Alabama.

Results
Nine questionnaires were undeliverable; of the remaining 211 surveys, 29 were returned (for a response rate of 13.7%), and 26 of those were usable. The results were consistent with other studies. All respondents focused on pediatrics; most were medical homes experienced with children having sensorineural hearing loss. Less than half had counseled families about CIs but had patients using them. Over half had not recommended CIs in 5 years. Several were unsure about current EHDIP goals and CIs in children. Over half were completely uncomfortable determining children’s CI candidacy but were comfortable referring them to specialists. About a third were completely uncomfortable discussing CIs with and counseling families about them; most were comfortable with CIs being used in children over other habilitative options.

Conclusions
These pediatricians demonstrated deficits in current, accurate knowledge about EHDIPs and CIs in children. Audiologists should help them obtain needed information.
Universal Newborn Hearing Screening Follow-Up: A University Clinic Perspective
Authors: Krishnan Lata A. 
Published: December 2009

PurposeTo evaluate the referral and follow-up procedures at a university clinic to determine whether the early intervention program is achieving the goals of diagnosis of hearing loss by 3 months, amplification within 1 month of diagnosis, and intervention services by 6 months, as outlined in the Joint Committee on Infant Hearing (JCIH; 2007) position statement.MethodFiles for 142 infants were examined, and the following data were collected from each file: date of birth, birth hospital, hometown, parents' ages, ethnicity, nursery status (well baby or neonatal intensive care unit), medical history, age at initial evaluation and at diagnosis, results of evaluation(s), and age at hearing aid fitting and start of early intervention services.ResultsResults revealed that 17% of infants were older than 3 months at the initial evaluation, and 18% of infants who needed further evaluation were lost to follow-up. None of the infants identified with hearing loss received amplification within 1 month of diagnosis or early intervention services by the age of 6 months.ConclusionsThe findings provide further evidence of the challenges of early intervention programs as stated by the JCIH (2007), and they emphasize the importance of communication between practitioners and implementation of monitoring systems and checks and balances to improve the efficacy of early intervention programs.
Effects of Syntactic Complexity and Sentence-Structure Priming on Speech Initiation Time in Adults Who Stutter
Authors: Tsiamtsiouris Jim , Cairns Helen Smith 
Published: December 2009

PurposeTo test the hypotheses that adults who stutter will be slower in producing syntactically complex sentences than fluent adults and will benefit more from sentence-structure priming than will fluent adults.MethodAdults who stutter (n= 15) and fluent adults (n= 15) participated in 2 experiments. In Experiment 1, adults in both groups were administered a task that required memorization and production of sentences that varied in syntactic complexity. The same individuals who participated in Experiment 1 also participated in Experiment 2. The second experiment required all participants to create and produce sentences under primed and unprimed sentence-structure conditions.ResultsRelative to adults who do not stutter, the speech initiation time of fluent utterances of adults who stutter became increasingly slower as syntactic complexity increased, and they exhibited greater facilitative effects of sentence-structure priming. In addition, adults who stutter showed a significant correlation between syntactic complexity and priming facilitation.ConclusionData from these experiments confirmed both hypotheses and provided evidence that a subgroup of adults who stutter have grammatical encoding differences when compared with adults who do not stutter.
Relief of Acquired Stuttering Associated With Parkinson’s Disease by Unilateral Left Subthalamic Brain Stimulation
Authors: Walker Harrison C. , Phillips Daniel E. , Boswell Deborah B. , Guthrie Barton L. , Guthrie Stephanie L. , Nicholas Anthony P. , Montgomery Erwin B. , Watts Ray L. 
Published: December 2009

PurposeIn this article, the authors report a case of acquired stuttering associated with Parkinson’s disease (PD) that was responsive to unilateral subthalamic nucleus deep-brain stimulation (STN DBS) in the language-dominant hemisphere.MethodA single-subject, masked, multiple baseline design was used to evaluate the effects of unilateral left STN DBS on stuttering associated with PD. The patient underwent 3 formal speech assessments of spontaneous speech and the reading of passages with DBS off and on. Speech samples were videotaped and placed in random order, and 2 independent speech-language pathologists calculated the percentage of stuttered syllables and classified individual stuttering events.ResultsStuttering improved significantly in the DBS-on condition. In total, 10% of syllables were affected by stuttering events with DBS off, and less than 1% of syllables were affected by stuttering events with DBS on (n= 2,281 syllables,p< .00001, in a χ2test). The effect of unilateral STN DBS on stuttering was relatively independent of whether the patient was on or off dopaminergic medications.ConclusionThis article emphasizes the important role of the subthalamic region in the motor control of speech and language.
Acoustic and Articulatory Features of Diphthong Production: A Speech Clarity Study
Authors: Tasko Stephen M. , Greilick Kristin 
Published: December 2009

Purpose
The purpose of this study was to evaluate how speaking clearly influences selected acoustic and orofacial kinematic measures associated with diphthong production.

Method

Forty-nine speakers, drawn from the University of Wisconsin X-Ray Microbeam Speech Production Database (J. R. Westbury, 1994), served as participants. Samples of clear and conversational productions of the word
combine
were extracted for analysis. Analyses included listener ratings of speech clarity and a number of acoustic and articulatory kinematic measures associated with production of the diphthong /aI/.

Results
Key results indicate that speaking clearly is associated with (a) increased duration of diphthong-related acoustic and kinematic events, (b) larger F1 and F2 excursions and associated tongue and mandible movements, and (c) minimal evidence of change in formant transition rate.

Conclusions
Overall, the results suggest that clarity-related changes in diphthong production are accomplished through larger, longer, but not necessarily faster diphthong-related transitions. The clarity-related adjustments in diphthong production observed in this study conform to a simple model that assumes speech clarity arises out of reduced overlap of articulatory gestures.
A Comparative Study of Two Acoustic Measures of Hypernasality
Authors: Vogel Adam P. , Ibrahim Hasherah M. , Reilly Sheena , Kilpatrick Nicky 
Published: December 2009

Purpose
This study aimed to compare 2 quantitative acoustic measures of nasality in children with cleft lip and palate (CLP) and healthy controls using formalized perceptual assessment as a guide.

Method
Fifty participants (23 children with CLP and 27 age- and gender-matched healthy controls) aged between 4 and 12 years produced a variety of high and low vowels that allowed perceptual ratings of nasal resonance severity as well as acoustic analysis of spectral changes. Two objective measures of nasality were used: 1/3 octave spectra analysis and the voice low tone high tone ratio. Each respective technique has been evaluated in previous research, and their potential as an effective means of detecting changes in nasal resonance has been demonstrated.

Results

Only 1/3 octave spectra analysis differentiated between participants with hypernasal speech and those perceived to have normal nasal resonance. Significant differences were also observed between varying levels of perceived severity on vowels within nonnasalized phonemic environments (/p
i
t/, /t
i
p/).

Conclusions
Perceptual judgment remains the primary means of evaluating levels of nasality in children with CLP. However, the development and validation of easy-to-use objective techniques remains an important goal for effective clinical and empirical practice.
The Perception of Lexical Tone Contrasts in Cantonese Children With and Without Specific Language Impairment (SLI)
Authors: Wong Anita M.-Y. , Ciocca Valter , Yung Sun 
Published: December 2009

Purpose
This study examined the perception of fundamental frequency (f0) patterns by Cantonese children with and without specific language impairment (SLI).

Method
Participants were 14 five-year-old children with SLI, and 14 age-matched (AM) and 13 four-year-old vocabulary-matched (VM) controls. The children identified a word from familiar word pairs that illustrated the 8 minimally contrastive pairs of the 6 lexical tones. They discriminated the f0 patterns within contrastive tonal pairs in speech and nonspeech stimuli.

Results
In tone identification, the SLI group performed worse than the AM group but not the VM group. In tone discrimination, the SLI group did worse than the AM group on 2 contrasts and showed a nonsignificant trend of poorer performance on all contrasts combined. The VM group generally did worse than the AM group. There were no group differences in discrimination performance between speech and nonspeech stimuli. No correlation was found between identification and discrimination performance. Only the normal controls showed a moderate correlation between vocabulary scores and performance in the 2 perception tasks.

Conclusion
The SLI group’s poor tone identification cannot be accounted for by vocabulary knowledge alone. The group’s tone discrimination performance suggests that some children with SLI have a deficit in f0 processing.