bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Prospective Study of Ventilator-Associated Pneumonia in Children
Authors: Srinivasan Ramya , Asselin Jeanette , Gildengorin Ginny , Wiener-Kronish J. , Flori H.R. 
Published: March 2009

OBJECTIVE. We conducted a prospective, observational study in a tertiary care pediatric center to determine risk factors for the development of and outcomes from ventilator-associated pneumonia.
METHODS. From November 2004 to June 2005, all NICU and PICU patients mechanically ventilated for &gt;24 hours were eligible for enrollment after parental consent. The primary outcome measure was the development of ventilator-associated pneumonia, which was defined by both Centers for Disease Control and Prevention/National Nosocomial Infections Surveillance criteria and clinician diagnosis. Secondary outcome measures were length of mechanical ventilation, hospital and ICU length of stay, hospital cost, and death.
RESULTS. Fifty-eight patients were enrolled. The median age was 6 months, and 57% were boys. The most common ventilator-associated pneumonia organisms identified were Gram-negative bacteria (42%), Staphylococcus aureus (22%), and Haemophilus influenzae (11%). On multivariate analysis, female gender, postsurgical admission diagnosis, presence of enteral feeds, and use of narcotic medications were associated with ventilator-associated pneumonia. Patients with ventilator-associated pneumonia had greater need for mechanical ventilation (12 vs 22 median ventilator-free days), longer ICU length of stay (6 vs 13 median ICU-free days), higher total median hospital costs ($308534 vs $252652), and increased absolute hospital mortality (10.5% vs 2.4%) than those without ventilator-associated pneumonia.
CONCLUSIONS. In mechanically ventilated, critically ill children, those with ventilator-associated pneumonia had a prolonged need for mechanical ventilation, a longer ICU stay, and a higher mortality rate. Female gender, postsurgical diagnosis, the use of narcotics, and the use of enteral feeds were associated with an increased risk of developing ventilator-associated pneumonia in these patients.
Exhaled Breath Condensate pH in Adult Croatian Population Without Respiratory Disorders: How Healthy a Population Should Be to Provide Normative Data?
Authors: Varnai Veda , Ljubičić Anita , Prester Ljerka , Macan Jelena 
Published: March 2009

Exhaled Breath Condensate pH in Adult Croatian Population Without Respiratory Disorders: How Healthy a Population Should Be to Provide Normative Data?
The aim of this study was to obtain preliminary exhaled breath condensate (EBC) pH values for healthy adult Croatian subjects, and to evaluate criteria for defining respiratory health of population providing normal EBC pH values in epidemiologic studies. In 109 adults without a history of lower airway symptoms (AS), four groups were described by narrowing the definition of "health" down to 1) without lower AS; 2) without lower and upper AS; 3) without AS, with normal FEV1 and bronchial normoreactivity; 4) without AS, with normal FEV1, bronchial normoreactivity, normal total IgE, and with negative skin prick test. Median EBC pH values did not differ between the groups (7.72, 7.73, 7.73, 7.73), but as health criteria got stricter, we observed a slight, nonsignificant increase in minimal pH values (6.95, 7.10, 7.20, 7.37). Median EBC pH values with interquartile range in the total sample (7.72; 7.63 to 7.76) were within the range previously reported by other authors. They did not differ regarding sex, smoking habit and atopic status, and were not associated with age, FEV1 or total IgE. The non-significant trend in EBC pH observed with stricter criteria of respiratory health and atopic status indicates the need for further research on criteria for defining healthy population in a larger sample.
Removal by laparoscopic partial ovariohysterectomy of a uterine leiomyoma assumed to have caused fetal death in a mare
Authors: Heijltjes J. M. , Rijkenhuizen A. B. M. , Hendriks W. K. , Stout T. A. E. 
Published: March 2009

SummaryA 13‐year‐old pluriparous Dutch Warmblood mare presented to Utrecht University's Department of Equine Sciences 4 weeks after suspected abortion at 3.5 months gestation, to investigate the nature of a uterine mass and persistent vulval discharge. Transrectal ultrasonographic examination revealed copious flocculent fluid and fetal remnants within the uterus and a 5–6 cm heterogenous mass in the uterine wall at the tip of the right horn. Expulsion of fetal parts and resolution of the coexisting endometritis were effected by a combination of repeated PGF2aanalogue injections to induce oestrus, application of PGE2gel to aid cervical relaxation, and daily uterine lavage and antibiotic instillation. The presence of the mass in the uterine wall was confirmed by hysteroscopy and the suspected tumour subsequently removed by partial laparoscopic ovariohysterectomy under standing sedation and local anaesthesia. The histological appearance of the tumour was consistent with a leiomyoma or moderately malignant leiomyosarcoma. Although a follow‐up examination 6 months post surgery revealed uncomplicated healing of the uterus, the owner decided to retire the mare from breeding. Uterine neoplasia is an extremely unusual cause of fetal death in the mare but, in the present case, laparoscopic partial ovariohysterectomy proved a promising, minimally invasive technique for salvaging sufficient uterus to make subsequent breeding a realistic proposition.
Reliability of intraoperative high-resolution 2D ultrasound as an alternative to high–field strength MR imaging for tumor resection control: a prospective comparative study
Authors: Gerganov Venelin Miloslavov , Samii Amir , Akbarian Arasch , Stieglitz Lennart , Samii Madjid , Fahlbusch Rudolf 
Published: March 2009

Object
Ultrasound may be a reliable but simpler alternative to intraoperative MR imaging (iMR imaging) for tumor resection control. However, its reliability in the detection of tumor remnants has not been definitely proven. The aim of the study was to compare high-field iMR imaging (1.5 T) and high-resolution 2D ultrasound in terms of tumor resection control.

Methods
A prospective comparative study of 26 consecutive patients was performed. The following parameters were compared: the existence of tumor remnants after presumed radical removal and the quality of the images. Tumor remnants were categorized as: detectable with both imaging modalities or visible only with 1 modality.

Results
Tumor remnants were detected in 21 cases (80.8%) with iMR imaging. All large remnants were demonstrated with both modalities, and their image quality was good. Two-dimensional ultrasound was not as effective in detecting remnants < 1 cm. Two remnants detected with iMR imaging were missed by ultrasound. In 2 cases suspicious signals visible only on ultrasound images were misinterpreted as remnants but turned out to be a blood clot and peritumoral parenchyma. The average time for acquisition of an ultrasound image was 2 minutes, whereas that for an iMR image was ~ 10 minutes. Neither modality resulted in any procedure-related complications or morbidity.

Conclusions
Intraoperative MR imaging is more precise in detecting small tumor remnants than 2D ultrasound. Nevertheless, the latter may be used as a less expensive and less time-consuming alternative that provides almost real-time feedback information. Its accuracy is highest in case of more confined, deeply located remnants. In cases of more superficially located remnants, its role is more limited.
Development of depth hoar and its effect on stable oxygen isotopic content in snow–firn stratigraphy on Ürümqi glacier No. 1, eastern Tien Shan, China
Authors: Feiteng Wang , Zhongqin Li , Huilin Li , Mingjun Zhang , Wenbin Wang , Lin Wang 
Published: March 2009

AbstractWe report on the development of depth hoar and its relation to stable oxygen isotopic content in snow–firn stratigraphy in the percolation zone of Ürümqi glacier No. 1, eastern Tien Shan, China, during the period September 2004–August 2006. The essential condition for the development of depth hoar in the snow–firn pack is the temperature gradient. When the temperature gradient of the snow–firn pack reaches a maximum value of 13.0˚Cm–1 in mid-October, depth hoar begins to develop. By the end of March, the depth hoar might account for 25% of the total snow–firn pack depth. From April to June, as the weather becomes warm, the transport of water vapor diminishes and melting– regelation metamorphism replaces metamorphism caused by the temperature gradient. As a result, the depth hoar turns into coarse-grained firn. Fractionation of the oxygen isotopic content also occurs during formation of the depth hoar. The bottom 15 cm of the depth-hoar δ18O values were depleted in the lighter isotopic species as the snow sublimated from the lower to the upper crystals, and the δ values increased from –9.4% to –7.0% from 8 September 2004 to 25 January 2005. The upper 10 cm of the depth-hoar δ18O values were enriched in the lighter isotopic species and the δ values decreased from –6.8% to –9.3% during the same period.
Magnetic Resonance Imaging of the Hand in Systemic Sclerosis
Authors: LOW ANDREA H.L. , LAX MATTHEW , JOHNSON SINDHU R. , LEE PETER 
Published: March 2009

Objective.To evaluate the utility of magnetic resonance imaging (MRI) in systemic sclerosis (SSc)-associated arthropathy.Methods.MRI of the hand was performed in patients presenting with joint pain/swelling in order (1) to determine the frequency of inflammation on MRI, and (2) to compare MRI with radiography.Results.Of 17 patients with SSc, 10 (59%) had inflammatory MRI findings with synovitis (n = 8), erosions (n = 7), joint effusion (n = 7), or tenosynovitis (n = 8). Bone edema was present in 9 patients. Of 7 patients with MRI erosions, only 2 had radiographic erosions.Conclusion.Our study illustrates the usefulness of MRI in the accurate diagnosis and characterization of SSc-associated arthropathy.
Variation in P2RX7 candidate gene (rs2230912) is not associated with bipolar I disorder and unipolar major depression in four European samples
Authors: Grigoroiu‐Serbanescu Maria , Herms Stefan , Mühleisen Thomas W. , Georgi Alexander , Diaconu Carmen C. , Strohmaier Jana , Czerski Piotr , Hauser Joanna , Leszczynska‐Rodziewicz Anna , Jamra Rami Abou , Babadjanova Gulia , Tiganov A. , Krasnov V. , Kapiletti Sofia , Neagu Ana Iulia , Vollmer Jennifer , Breuer René , Rietschel Marcella , Nöthen Markus M. , Cichon Sven , Propping Peter 
Published: March 2009

AbstractTwo recent studies reported evidence for association between genetic variation of the positional candidate gene P2RX7 on chromosome 12q24 and bipolar I disorder (BPI) [Barden et al. (2006); Am J Med Genet Part B 141B:374–382; McQuillin et al. (2008); Mol Psychiatry 13:1‐7] and one study found association with unipolar major depression (Mdd‐UP) [Lucae et al. (2006); Hum Mol Genet 15:2438–2445]. In the present work, we aimed to replicate the SNP that showed the strongest association in the above‐mentioned studies, namely rs2230912 (P2RX7‐E13A) resulting in a change of the amino acid glutamine to arginine at position 460 (Gln460Arg), in four European bipolar I disorder samples from Germany, Poland, Romania, and Russia totaling 1,445 patients, in a German sample of recurrent Mdd‐UP patients (N = 640), and a control sample of 2,006 subjects. We found no allelic or genotypic association between rs2230912 and BPI or Mdd‐UP both in the national samples and in the combined European patient sample. Additional studies are needed to clarify the potential involvement of P2RX7 and of SNP rs2230912 in the etiology of major affective disorders. © 2009 Wiley‐Liss, Inc.
Chirality Change of Chloronitrobenzene on Au(111) Induced by Inelastic Electron Tunneling
Authors: Simic‐Milosevic Violeta , Meyer Jörg , Morgenstern Karina 
Published: March 2009

AbstractChirality chameleon: Inelastic electron tunneling manipulation can be used to change a single chloronitrobenzene (ClNB) molecule, randomly adsorbed on Au(111), into its desired enantiomeric form (r or l, see STM images and ball‐and‐stick representation) and to vary its rotational orientation. The different threshold voltages for chirality change (260 mV) and rotation (380 mV) allow these processes to be induced separately.magnified image
Preparation and characterization of poly(butylene terephthalate) nanocomposites with various organoclays
Authors: Nirukhe Ashwini B. , Shertukde V. V. 
Published: March 2009

AbstractLayered‐silicate‐based polymer–clay nanocomposite materials were prepared depending on the surface modification of montmorillonite (MMT). Nanocomposites consisting of poly(butylene terephthalate) (PBT) as a matrix and dispersed inorganic clay modified with cetyl pyridinium chloride (CPC), benzyl dimethyl N‐hexadecyl ammonium chloride, and hexadecyl trimethyl ammonium bromide by direct melt intercalation were studied. The organoclay loading was varied from 1 to 5 wt %. The organoclays were characterized with X‐ray diffraction (XRD) to compute the crystallographic spacing and with thermogravimetric analysis to study the thermal stability. Detailed investigations of the mechanical and thermal properties as well as a dispersion study by XRD of the PBT/clay nanocomposites were conducted. X‐ray scattering showed that the layers of organoclay were intercalated with intercalating agents. According to the results of a differential scanning calorimetry analysis, clay acted as a nucleating agent, affecting the crystallization. The PBT nanocomposites containing clay treated with CPC showed good mechanical properties because of intercalation into the polymer matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The evolutionary context of robust and redundant cell biological mechanisms
Authors: Delattre Marie , Félix Marie‐Anne 
Published: March 2009

AbstractThe robustness of biological processes to perturbations has so far been mainly explored in unicellular organisms; multicellular organisms have been studied for developmental processes or in the special case of redundancy between gene duplicates. Here we explore the robustness of cell biological mechanisms of multicellular organisms in an evolutionary context. We propose that the reuse of similar cell biological mechanisms in different cell types of the same organism has evolutionary implications: (1) the maintenance of apparently redundant mechanisms over evolutionary time may in part be explained by their differential requirement in various cell types; (2) the relative requirement for two alternative mechanisms may evolve among homologous cells in different organisms. We present examples of cell biological processes, such as centrosome separation in prophase, spindle formation or cleavage furrow positioning, that support the first proposition. We propose experimental tests of these hypotheses.
Classification of sequence signatures: a guide to Hox protein function
Authors: Merabet Samir , Hudry Bruno , Saadaoui Mehdi , Graba Yacine 
Published: March 2009

AbstractHox proteins are part of the conserved superfamily of homeodomain‐containing transcription factors and play fundamental roles in shaping animal body plans in development and evolution. However, molecular mechanisms underlying their diverse and specific biological functions remain largely enigmatic. Here, we have analyzed Hox sequences from the main evolutionary branches of the Bilateria group. We have found that four classes of Hox protein signatures exist, which together provide sufficient support to explain how different Hox proteins differ in their control and function. The homeodomain and its surrounding sequences accumulate nearly all signatures, constituting an extended module where most of the information distinguishing Hox proteins is concentrated. Only a small fraction of these signatures has been investigated at the functional level, but these show that approaches relying on Hox protein alterations still have a large potential for deciphering molecular mechanisms of Hox differential control.
Analytical effectiveness calculations concerning the formation of an inhibitive fermentation product associated with growth of biomass films immobilized in or around carriers
Authors: Van Ede C. J. , Dijkman H. , Beenackers A. A. C. M. 
Published: March 2009

AbstractA reaction engineering model is presented for the bioproduction of chemicals associated with the growth of immobilized biomass in or around carriers. The model describes multiple‐substrate diffusion limitations and first‐order growth inhibition by one of the products.Analytical solutions are presented for intra‐biofilm substrate and product concentrations, active biofilm thickness, biocatalyst effectiveness factor and degree of catalyst utilization. Simple criteria for optimal catalyst design are derived. Where applicable, the presented explicit analytical solutions for the biocatalyst effectiveness factor are much more convenient to incorporate into a macro‐reactor model than the numerical alternatives.
An empirical mixing rule for estimating mean ionic activity coefficients in multielectrolyte solutions from binary data only
Authors: Haghtalab A. , Vera J. H. 
Published: March 2009

AbstractAn empirical mixing rule is proposed for mean ionic activity coefficient of electrolytes in multielectrolyte mixtures. The mean activity coefficients are calculated from data of the constituent binary single‐salt water solutions only. Using the mixing rule, the trace mean activity coefficients and the Harned's coefficients of electrolytes in ternary mixtures with and without a common ion are predicted and compared with literature data. The agreement of the calculated values with the experimental data is very good, particularly for systems which follow Brönsted ion interaction theory. Calculations for sea water are presented as example for multielectrolyte systems. The predictions agree well with experimental data.
Liquid holdup in gas‐liquid cocurrent downflow through packed beds
Authors: Venkata Ratnam G. S. , Varma Y. B. G. 
Published: March 2009

AbstractThe average in situ volume fraction of the liquid phase for gas‐liquid cocurrent downflow through packed beds is correlated to the input volume fraction of the liquid and the bed geometry. The range of operation is delineated into a high‐interaction regime and a low‐interaction regime based on the influence of the gas rate on the liquid holdup. Experimental data of the present investigation using air‐water and air‐CMC solutions, as well as that reported in literature covering a wide range in variables, are considered in the development of correlations for total and dynamic liquid holdup.
Fed‐batch digestion of insoluble solid‐state substrates
Authors: Huang Shih‐Yow , Chou Ming‐Shean 
Published: March 2009

AbstractPerformance equations for the fed‐batch digestion of insoluble solid‐state substrates were developed based on a verified interfacial kinetic model for microbial uptake of these substrates. Fed‐batch anaerobic digestions of a suspension of stearic acid with a mean particle size of 2 μm were conducted to verify the derived equations. Agreement between the experimental and calculated results indicated the validity of these equations. The performance equations should be useful for describing the time courses of cell growth, substrate consumption and product accumulation in a fed‐batch digestion system with insoluble solid‐state organics as substrate.
Distribution des temps de séjour en écoulement tourbillonnaire annulaire induit par une entrée tangentielle du liquide
Authors: Legentilhomme P. , Legrand J. 
Published: March 2009

AbstractCe travail est consacré à la modélisation globale, à partir de la détermination expérimentale de la distribution des temps de séjour, de l'écoulement dans une cellule annulaire équipée de différents systèmes d'alimentation, pour des nombres de Reynolds compris entre 100 et 5000. En utilisant le modèle piston avec dispersion axiale, puis par l'association en série de réacteurs piston et parafaitement agité, nous montrons que l'écoulement tourbillonnaire non‐entretenu produit par une entrée tangentielle présente un caractère piston très prononcé, associé à une zone agitée due au système d'entrée‐sortie du fluide dans la cellule. L'utilisation d'une entrée axiale ou perpendiculaire à la cellule diminue le pourcentage du volume total du réacteur siège d'un écoulement piston par rapport à celui déterminé en employant une entrée tangentielle.
Prediction of heat transfer to liquid‐solid fluidized beds
Authors: Jamialahmadi M. , Malayeri M. R. , Müller‐Steinhagen H. 
Published: March 2009

AbstractHeat transfer coefficients to a liquid‐solid fluidized bed in a cylindrical tube have been measured using water as liquid phase and three types of cylindrical steel particles, as well as glass, nickel, copper and lead spheres of different sizes as solid phase. The independent varaibles included heat flux, liquid velocity and particle physical properties. The experimental results as well as a data bank containing a large number of measured heat transfer coefficients for solid‐liquid fluidization over a wide range of operational parameters have been compared with the predictions of most published correlations. A model for the prediction of heat transfer coefficients is proposed which predicts the present experimental data and the data of other investigators with good accuracy.
Isoelectric precipitation of sunflower protein in a tubular precipitator
Authors: Raphael M. , Rohani S. , Sosulski F. 
Published: March 2009

AbstractIsoelectric precipitation of sunflower protein was carried out in a 10‐m long, 6‐mm internal diameter glass tubular precipitator. The effects of feed flow rate, protein concentration in the feed stream, and volumetric feed ratio of precipitant (HCl aqueous solution) to protein solution on solid protein recovery and particle size distribution were studied. The dispersion range of the tubular precipitator was modelled to predict the experimental results. Calculated initial growth rates of protein particles were found to: increase with increases in feed flow rate and protein concentration in the feed stream, and decrease with increases in volumetric feed ratio.
Determination of minimum fluidization velocity by pressure fluctuation measurement
Authors: Wilkinson Derek 
Published: March 2009

AbstractUsing the standard deviation of pressure fluctuations to find the minimum fluidization velocity, Umf, avoids the need to de‐fluidize the bed so Umf, can be found for operational bubbling fluidized beds without disrupting the process provided only that the superficial velocity may be altered and that the bed remains in the bubbling fluidized state.This investigation has concentrated on two distinct aspects of the pressure fluctuation method for Umf determination: (1) the minimum number of pressure measurements required to obtain reliable estimates of standard deviation has been identified as about 10000 and (2) pressure fluctuation measurements in the plenum below the gas distributor are suitable for Umf determination so the problems of pressure probe clogging and erosion by bed particles may be avoided.
A two‐dimensional model for gas mixing in the upper dilute zone of a circulating fluidized bed
Authors: Kruse M. , Schoenfelder H. , Werther J. 
Published: March 2009

AbstractBased on measurements in a circulating fluidized test unit with a riser of 0.4 m i.d., a two‐dimensional two‐phase model for gas mixing has been developed. Radial gas dispersion and gas backmixing caused by dense clusters falling countercurrently to the main flow of a lean gas/solid suspension are considered. The model has successfully been compared with experimental data over a wide range of operating conditions. The model accounts for the main mixing phenomena and may be applied to calculations of chemical reactions in CFB risers.