bluuebunny/crossref_metadata_2025 huggingface dataset:
Low levels of exhaled nitric oxide are associated with impaired lung function in cystic fibrosis
Authors: Keen C. , Gustafsson P. , Lindblad A. , Wennergren G. , Olin A‐C.
Published: February 2010

Fraction of exhaled nitric oxide (FENO) is often reduced in cystic fibrosis (CF). FENO at different expiratory flows can provide an indication of the site of nitric oxide production. The aim of this study was to examine whether NO parameters are related to overall (FEV1) or peripheral (lung clearance index, LCI, measured by multiple breath SF6 washout) airway function and systemic inflammation in CF. Secondary aim was to compare alveolar NO and bronchial NO flux calculated by two different mathematical models, a linear and a nonlinear method. Thirty‐five healthy and 45 CF children were recruited. FENO at 50 ml/sec (FENO50) and bronchial NO flux were lower in CF than controls, 9.5 (2.7–38.8) (median (range)) versus 12.4 (5.2–40.1) ppb, P = 0.029, and 391 (97–1772) versus 578 (123–1993) (pl/sec), P = 0.036, respectively. No difference in alveolar NO was shown. The nonlinear method resulted in lower alveolar NO and higher bronchial flux, than the linear method, but the result was closely correlated in both groups. LCI was higher in CF than controls, 8.4 (6.5–12.9) versus 5.9 (5.1–7.8), P < 0.001. FENO50 was negatively correlated with LCI (r = −0.43; P = 0.003) and positively correlated with FEV1 (r = 0.42, P = 0.004) in CF. Alveolar NO correlated negatively with inflammatory markers: orosomucoid (r = −0.42, P = 0.005), platelets (r = −0.50, P < 0.001) and white blood cell count (r = −0.48, P = 0.001). In conclusion, FENO50 and bronchial NO flux are reduced in young CF subjects and low FENO50 is associated with overall and small airway obstruction. NO parameters derived from the different models were closely related but the values differed slightly. Pediatr Pulmonol. 2010; 45:241–248. © 2010 Wiley‐Liss, Inc.
Acid steatocrit determination is not helpful in cystic fibrosis patients without or with mild steatorrhea
Authors: Walkowiak Jarosław , Lisowska Aleksandra , Blask‐Osipa Anna , Drzymała‐Czyż Sławomira , Sobkowiak Paulina , Cichy Wojciech , Bręborowicz Anna , Herzig Karl‐Heinz , Radzikowski Andrzej
Published: February 2010

Background

Most methods used for the assessment of severe steatorrhea in cystic fibrosis (CF) are sensitive. In fact, the tests show their usefulness in a borderline zone of the results. Yet, the existing data related to acid steatocrit (AS) are still contradictory. Therefore, in the present study we have aimed to assess CF patients without or with mild steatorhea (<10 g/day) and evaluate the applicability of AS in such a subset of patients.

Patients and Methods

In fifty‐five CF patients, AS, fecal fat concentration (FFC) and fecal fat excretion (FFE) in 1‐day stool collection were assessed from one to three times (149 samples). In 50 subjects, FFC, FFE, and AS were available for 3 subsequent days. It allowed for the calculations based upon 3‐day fecal fat balance study.

Results

The correlations between FFE/FFC and AS based upon 1‐day stool collection, although statistically significant, were rather weak (r = 0.208, P < 0.011; r = 0.362, P < 0.000006, respectively). The correlations between FFE/FFC and AS based upon the 3‐day stool collection, although stronger, did not show values a linear relationship (r = 0.394, P < 0.005; r = 0.454, P < 0.001, respectively). With no regard to the cut‐off level for AS (10% and 20%), sensitivity, specificity, negative, and positive predictive values in the determination of abnormal FFC and FFE were not satisfactory. The flow charts describing the accuracy of AS to determine FFE and FC revealed a high level of uncertainty.

Conclusions

AS does not reflect in a reliable way FFE in CF patients without or mild steatorrhea. Its applicability in the assessment of FFC in such patients has therefore limited practical value. Pediatr Pulmonol. 2010; 45:249–254. © 2010 Wiley‐Liss, Inc.
Lung transplantation in children with idiopathic pulmonary arterial hypertension
Authors: Lammers Astrid E. , Burch Michael , Benden Christian , Elliott Martin J. , Rees Philip , Haworth Sheila G. , Aurora Paul
Published: February 2010

Background

Despite improved medical therapy, transplantation (Tx) represents the only option for end‐stage pulmonary vascular disease.

Methods

Clinical data of children with idiopathic pulmonary arterial hypertension (IPAH) referred for Tx assessment between January 2002 and June 2007 were related to listing decision and outcome.

Results

Seven of the 14 children assessed for Tx were listed. Five were transplanted (lung Tx, n = 3; heart–lung Tx, n = 2) and two died on the waiting list. Mean age at diagnosis was 3.7 (0.4–9.5) years. Time from diagnosis to listing was 3.6 years (range 1.4–9.3). Children listed were in a worse functional class (WHO 3.5 vs. 2.5; P = 0.0006), had a lower SpO2 on exercise (76.5% vs. 89%; P = 0.0001) and a shorter 6‐min walk distance (154 m vs. 330 m; P < 0.01) than those not listed. Right ventricular function was worse in those listed (P = 0.03), as was pulmonary vascular resistance index (PVRI) on vasodilator testing (34 U m2 vs. 14.6 U m2; P = 0.03). Age at diagnosis and at assessment, weight, height, mean pulmonary artery pressure, baseline PVRI, B‐type natriuretic peptide, spirometry and resting‐SO2 did not differ between the two groups. For the five children transplanted, median waiting time was 81 days. Age at Tx was 5.4 years. After 2.8 years all transplanted children are alive with a good functional outcome. Two patients died on the active waiting list. All children considered too well for listing are still alive and stable on treatment.

Conclusions

Outcome after transplantation in children with IPAH has been encouraging. Defining listing criteria for these patients remains a challenge. Pediatr Pulmonol. 2010; 45:263–269. © 2010 Wiley‐Liss, Inc.
How much do primary care givers know about tracheostomy and home ventilator emergency care?
Authors: Kun Sheila S. , Davidson‐Ward Sally L. , Hulse Linda M. , Keens Thomas G.
Published: February 2010

Children on home mechanical ventilation are a high‐risk population. How much do primary caregivers (PC) know about handling unexpected situations with tracheostomies or malfunction of their ventilators? To answer this, we prospectively studied the knowledge of 152 PC (108 parents and 44 nurses), using a 25‐question survey regarding emergency situations at home. Results: their mean score was 20.2 correct answers (81%). However, 96 PC (63%) did not know that the low pressure ventilator alarm would not sound if the tracheostomy tube decannulated while still connected to the ventilator. Seventy‐nine PC (52%) failed to understand high pressure alarms sound and mucous plugging. Sixty‐six PC (43%) did not know how much power a battery stored after the suction machine was fully charged. Sixty‐one PC (40%) did not know when the low pressure or low minute volume alarm sounds. Fifty‐six PC (37%) relied on the ventilator alarm to determine the presence of mucous plugs. There were no significant differences in the scores of PC who used continuous flow ventilators, nor in English‐speaking PC versus Spanish‐speaking PC. The experience of the PC did not make a difference in their knowledge of HMV emergency care. Having professional training did not pose an advantage in the score for nurses. We conclude that most PC had a good understanding of emergency care. We speculate that more in depth education on the technical aspects of ventilator alarms and tracheal mucous plugging may help to reduce or prevent emergencies of children on HMV. Pediatr Pulmonol. 2010; 45:270–274. © 2010 Wiley‐Liss, Inc.
Lessons learned from a randomized trial of airway secretion clearance techniques in cystic fibrosis
Authors: Sontag Marci K. , Quittner Alexandra L. , Modi Avani C. , Koenig Joni M. , Giles Don , Oermann Christopher M. , Konstan Michael W. , Castile Robert , Accurso Frank J.
Published: February 2010

Rationale

Airway secretion clearance therapies are a cornerstone of cystic fibrosis care, however longitudinal comparative studies are rare. Our objectives were to compare three therapies [postural drainage and percussion: (postural drainage), flutter device (FD), and high frequency chest wall oscillation: (vest)], by studying (1) change in pulmonary function; (2) time to need for intravenous (IV) antibiotics, (3) use of pulmonary therapies, (4) adherence to treatment, (5) treatment satisfaction, and (6) quality of life.

Methods

Participants were randomly assigned to one of three therapies twice daily. Clinical outcomes were assessed quarterly over 3 years.

Results

Enrollment goals were not met, and withdrawal rates were high, especially in postural drainage (51%) and FD (26%), compared to vest (9%), resulting in early termination. FEV1 decline, time to need IV antibiotics, and other pulmonary therapies were not different. The annual FEF25–75% predicted rate of decline was greater in those using vest (P = 0.02). Adherence was not significantly different (P = 0.09). Overall treatment satisfaction was higher in vest and FD than in postural drainage (P < 0.05). Health‐related quality of life was not different. The rate of FEV1 decline was 1.23% predicted/year.

Conclusions

The study was ended early due to dropout and smaller than expected decline in FEV1. Patients were more satisfied with vest and FD. The longitudinal decline in FEF25–75% was faster in vest; we found no other difference in lung function decline, taken together this warrants further study. The slow decline in FEV1 illustrates the difficulty with FEV1 decline as a clinical trial outcome. Pediatr Pulmonol. 2010; 45:291–300. © 2010 Wiley‐Liss, Inc.
Multi‐Parameter Study of Nanoscale TiO2 and CeO2 Additives in Composite AP/HTPB Solid Propellants
Authors: Stephens Matthew A. , Petersen Eric L. , Carro Rodolphe , Reid David L. , Seal Sudipta
Published: February 2010

A statistical Taguchi L8 matrix was used to conduct a multi‐parameter study of the use of nanoscale additives in composite solid propellants. The additives studied were TiO2 (titania) and CeO2 (ceria). The other parameters involved in the experiment were the oxidizer loading and distribution, additive percentage and size, additive size (nano‐scale or μm‐scale), and the mixing method. Four baseline propellants without additives were also produced for comparison. The propellants were tested from 3.45 to 13.78 MPa in a strand bomb, and burning rate curves were determined for all formulas. By analyzing the Taguchi matrix, the sensitivity of each parameter according to the pressure sensitivity and burning rate of the propellant was calculated. The dominant factors depend on whether the additive is needed for modifying the pressure index or the absolute value of the burning rate. In general, the effectiveness of the additives was most influenced by oxidizer percentage, oxidizer size distribution, and additive type. The amount of additive, mixing method, and additive size all had relatively minor impacts on the effectiveness of the additives.
Preparation and Properties of HMX Coated with a Composite of TNT/Energetic Material
Authors: An Chongwei , Wang Jingyu , Xu Wenzheng , Li Fengsheng
Published: February 2010

To improve the safety of HMX without sacrificing energy properties, the composites of TNT and an energetic material (HP‐1) were used to coat HMX particles by a method of integrating solvent–nonsolvent with aqueous suspension‐melting. SEM (scanning electron microscopy) and XPS (X‐ray photoelectron spectrometry) were employed to characterize the samples. The effect of the processing parameters, such as mass ratio of HP‐1 to TNT (MRHT), stirring speed, and cooling rate, on the quality of coated samples were investigated and discussed. The mechanical sensitivity, thermal sensitivity, thermal decomposition characteristic, and heat of detonation of raw and coated HMX samples were also measured and contrasted. Results show that when MRHT, stirring speed in the second stage and cooling rate are 1 : 5, 1000 r⋅min−1 and 5 °C⋅min−1 respectively, the optimal coating effect is achieved. Compared with that of raw HMX, both impact and friction sensitivity of HMX coated with 2.5 wt.‐% TNT and 0.5 wt.‐% HP‐1 decrease obviously, whereas there is a slight change in their thermal sensitivity and thermal decomposition characteristics. Meanwhile, such surface coating does not result in the decrease of its energy properties.
Spinosad resistance development in wild olive fruit fly Bactrocera oleae (Diptera: Tephritidae) populations in California
Authors: Kakani Evdoxia G , Zygouridis Nikos E , Tsoumani Konstantina T , Seraphides Nicos , Zalom Frank G , Mathiopoulos Kostas D
Published: February 2010

BACKGROUND: Among target pests of the insecticide spinosad is the olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae). In Cyprus, spinosad has been sporadically used since its registration in 2002, whereas in Greece its use has been very limited since its registration in 2004, particularly in biological olive cultivars in Crete. By contrast, in California it has been the only insecticide used against the olive fruit fly since its registration in 2004. This study aimed at examining the resistance status of the olive fruit fly to spinosad.

RESULTS: Populations from California, Greece and Cyprus, plus a laboratory population, were tested. Bioassays were performed by oral or topical application of different concentrations of the insecticide. Cypriot populations demonstrated no resistance as compared with that of the laboratory population. Among the Greek populations, only one from Crete demonstrated a fourfold increase in resistance, whereas five populations from California demonstrated a 9–13‐fold increase.

CONCLUSION: The observed resistance increase was associated with spinosad applications in the respective areas. These values are relatively low and do not yet pose a serious control problem in the field. However, the observed variation documents that spinosad tolerance has increased in areas where the insecticide has been more extensively used. Copyright © 2010 Society of Chemical Industry
Effect of plasma power on properties of a‐SiC:H films deposited by DC magnetron sputtering
Authors: Brighet Amer , Mokkadem Kamel , Fedala Abdelkarim , Kechouane Mohamed
Published: February 2010

The effect of plasma discharge power on the properties of a‐SiC:H thin films deposited by DC magnetron sputtering from the use of a liquid source based on hydrocarbon (triméthylphosphine: TMP, (P(CH3)3) are presented. The liquid source based of trimethylphosphine is introduced into the deposit chamber by using hydrogen as carrying gas. The samples were characterized by optical transmission, infrared absorption (FT‐IR) and electrical conductivity measurements. Optical transmission showed that the increase of the plasma discharge power induced a decrease in optical gap energy value accompanied by an increase of refractive index due to a reduction of Si‐H bonds and the carbon film content. Infra‐red absorption measurements clearly evidenced the appearance of additional bands relating to the constituent elements of the TMP (H, C, P). In the same way, a reduction in the phosphorus and carbon contents with the increase of the discharge power is observed. The electrical conductivity measurements have revealed a change of electrical properties of a‐Si:H(P) layers and the doping efficiency with the plasma power. They also clearly evidenced carbon incorporation in a‐Si:H matrix which limits the phosphorus doping effectiveness. The effect of the annealing temperature on the electric photoconductivity of material was also studied. We clearly evidenced that the a‐SiC:H(P) films are photoconductive with an improvement after a thermal annealing in the range of 130–250 °C correlated with an activation of the phosphorus atoms in the a‐Si:H matrix. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Boson peak in low‐frequency Raman spectra of AsxS100‐x glasses: nanocluster contribution
Authors: Holomb Roman , Mitsa Volodimir , Johansson Patrik , Veres Miklos
Published: February 2010

The origin of the Boson peak was investigated using Raman spectroscopy and ab initio calculations. Low frequency Raman active vibrational modes of different branchy‐, ring‐ and cage‐like AsmSn nanoclusters were calculated and compared to experimentally determined Raman spectra of AsxS100‐x glasses with different compositon. A good correlation was found between the spectral features and the calculated Raman modes. The possible structural nature of the Boson peak in arsenic chalcogenides is proposed and discussed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microcrystalline silicon n‐i‐p solar cells prepared with microcrystalline silicon oxide (μc‐SiOx:H) n‐layer
Authors: Smirnov Vladimir , Böttler Wanjiao , Lambertz Andreas , Wang Haiyan , Carius Reinhard , Finger Friedhelm
Published: February 2010

N‐type hydrogenated microcrystalline silicon oxide (μc‐SiOx:H) layers were used as window layers in n‐side illuminated microcrystalline silicon n–i–p solar cells. Optical, electrical and structural properties of μc‐SiOx:H films were investigated by Photothermal Deflection Spectroscopy, conductivity and Raman scattering measurements. μc‐SiOx:H layers were prepared over a range of carbon dioxide (CO2) flow and film thickness, and the effects on the solar cell performance were investigated. By optimising the μc‐SiOx:H window layer properties, an improved short‐circuit current density of 23.4 mA/cm2 is achieved, leading to an efficiency of 8.0% for 1μm thick absorber layer and Ag back contact. The correlation between cell performance and μc‐SiOx:H layer properties is discussed. The results are compared to the performance of solar cells prepared with alternative optimised window layers. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ab initio calculations and the effect of atomic substitution in the Raman spectra of As(Sb,Bi)2S3 films
Authors: Kondrat Olexandr , Popovich Natalija , Holomb Roman , Mitsa Volodimir , Petrachenkov Olexandr , Koós Margit , Veres Miklos
Published: February 2010

The comparative analysis of the calculated and experimental Raman spectra of non‐crystalline As2S3, Bi2S3 and Sb2S3 films (i.e. with exchanging As to Sb, Bi) obtained by flash evaporation on glassy and silicon substrates was performed. The spectra were interpreted and analysed using the results of molecular modelling and ab initio calculations. The structural models used for calculations include both basic building blocks and other types of atomic clusters known for As‐S, Bi‐S, and Sb‐S binary systems. The influence of atomic substitution on the nanostructure of flash evaporated As(Sb,Bi)2S3 films were investigated, observed photo‐induced phenomena and related peculiarities were analysed using results of ab initio calculations and discussed in detail. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microscopic study of carrier transport in the organic semiconductor zinc‐phthalocyanine
Authors: Duarte João Piroto , Alberto Helena Vieira , Vilão Rui César , Gil João M. , Weidinger Alois , Campos Nuno Ayres de
Published: February 2010

Nominally undoped zinc‐phthalocyanine (ZnPc) was investigated using Muon Spin Rotation (μSR) to probe microscopic carrier transport properties. The study focused on the relaxation of the positive muon's polarisation produced by spin‐flip scattering with charge carriers. An energy of 71(8) meV was found for the temperature activation of carrier jumps, a value that does not match the activation energies known in ZnPc from electrical measurements, and that was attributed to a fast transport component in this material. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New developments in the fabrication of amorphous silicon photovoltaic modules on very large 2.60 m × 2.20 m glass
Authors: Vetter Michael , Borrajo Jacinto P. , Andreu Jordi
Published: February 2010

The fabrication of photovoltaic thin film modules based on hydrogenated amorphous silicon (a‐Si:H) technology on very large float glass is presented. In high volume manufacture of about 900 modules/day production present an average power of about 105 W ±5 W (initial state, 1.43 m2 modules). Light‐induced degradation (LID) of modules results in an average power of about 85±2 W after about 500 kWh of degradation. Degradation of the fill factor (FF) of current voltage curves under illumination is the main contributor to degradation reducing from about 70% to 60% (artificial light). The dependency of the power in the initial and in the degraded state on the intrinsic layer thickness of the pin‐structure is investigated. Thicker intrinsic layer results in higher initial power, however also the degradation rate is higher resulting in very similar power of all modules in the degradation state. LID is performed in in‐door conditions under metal‐halogen lamp light and in outdoor conditions with sun‐light. Under outdoor conditions the degraded state of the modules is not stable, but depends on the season, resulting in lower power in winter months and higher power in summer months. Main contributor to this effect is the change of short circuit current. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A study of metal contact properties on thermal annealed PECVD SiC thin films for MEMS applications
Authors: Oliveira Alessandro R. , Pereyra Inés , Carreño Marcelo N. P.
Published: February 2010

The investigation of metal contact properties of thermal annealed PECVD n‐type SiC thin films for micro‐electromechanical system (MEMS) is reported. The PECVD SiC films were annealed at 1200 °C during 2 hours to obtain poly 3C‐SiC, which is evidenced by the presence of (111) plane of 3C–SiC crystalline phase in the X‐ray diffraction (XRD) pattern and by strong and narrow Lorentzian SiC stretching peak in the FTIR spectra. Hall Effect measurements at room temperature demonstrate that these annealed phosphorus doped films are n‐type semiconductor with donor concentration of 6 × 1019 cm–3. The studied metals were titanium, aluminum and nickel. The metal to poly‐SiC contact were studied using the TLM technique. The three metals exhibited excellent I‐V linearly and showed ohmic characteristics at room temperature. In the best case, a specific resistance of 6 × 10–4 Ωcm2 was obtained for nickel contacts. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystallographic orientation dependent etching of graphene layers
Authors: Nemes–Incze Péter , Magda Gábor , Kamarás Katalin , Biró László Péter
Published: February 2010

Graphene has gripped the scientific community ever since its discovery in 2004, with very promising electronic properties and hopes to integrate graphene into nanoelectronic devices. For graphene to make its way into electronic devices, two major obstacles have to be overcome: reproducible preparation of large area graphene samples and patterning techniques to obtain functional components. In this paper we present a graphene etching technique, which is crystallographic orientation selective and allows for the patterning of graphene layers using a chemical reduction process. The process involves the reduction of the SiO2 support by the carbon in the graphene itself. This reaction only occurs at the sample edges and does not result in the degradation of the graphene crystal lattice itself. However, we have observed evidence of strong hole doping in our etched samples.

This etching technique opens up new possibilities in graphene patterning and modification. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The correlation structure of longitudinal measurements of vision in patients with macular degeneration
Authors: Burzykowski Tomasz , Buyse M.
Published: February 2010

Background: In age‐related macular degeneration (ARMD) trials, the FDA‐approved endpoint is the loss (or gain) of at least three lines of vision as compared to baseline. The use of such a response endpoint entails a potentially severe loss of information. A more efficient strategy could be obtained by using longitudinal measures of the change in visual acuity. In this paper we investigate, by using data from two randomized clinical trials, the mean and variance–covariance structures of the longitudinal measurements of the change in visual acuity.

Methods: Individual patient data were collected in 234 patients in a randomized trial comparing interferon‐α with placebo and in 1181 patients in a randomized trial comparing three active doses of pegaptanib with sham. A linear model for longitudinal data was used to analyze the repeated measurements of the change in visual acuity.

Results: For both trials, the data were adequately summarized by a model that assumed a quadratic trend for the mean change in visual acuity over time, a power variance function, and an antedependence correlation structure. The power variance function was remarkably similar for the two datasets and involved the square root of the measurement time.

Conclusions: The similarity of the estimated variance functions and correlation structures for both datasets indicates that these aspects may be a genuine feature of the measurements of changes in visual acuity in patients with ARMD. The feature can be used in the planning and analysis of trials that use visual acuity as the clinical endpoint of interest. Copyright © 2010 John Wiley & Sons, Ltd.
Individual and combined influence of El Niño–Southern Oscillation and Indian Ocean Dipole on the Tropospheric Biennial Oscillation
Authors: Pillai Prasanth A. , Mohankumar K.
Published: February 2010

Tropospheric biennial oscillation (TBO) is the tendency of a strong monsoon to be followed by a weaker one and vice versa. It involves both oceanic and atmospheric processes in the tropical Indian and Pacific Ocean regions. The present study analyses the effect of dynamical processes of the Indian and Pacific Oceans like the Indian Ocean Dipole (IOD) and El Niño–Southern Oscillation (ENSO) on the TBO. The 200 hPa velocity potential, 850 hPa zonal wind and sea‐surface temperature datasets obtained from NCEP/NCAR reanalysis for the period 1950–2006 are used for the study of the TBO. The IOD and TBO have both in‐phase (positive/negative IOD with positive/negative TBO) and out‐of‐phase (positive/negative IOD with negative/positive TBO) relationships. On the other hand, La Niña is associated with the positive phase of TBO and El Niño with the negative phase. In the presence of El Niño (La Niña), positive (negative) IOD is associated with negative (positive) TBO and in the absence of ENSO, positive (negative) IOD is associated with positive (negative) phase of TBO. When ENSO is associated with TBO, it tends to dominate the biennial transition irrespective of IOD. In‐phase Indian to Australian monsoon transition of TBO is controlled by ENSO. IOD–TBO association is strong and significant in the absence of ENSO only. The biennial reversal is confined to the Indian Ocean in the TBO cycle associated with IOD only. Thus IOD can be considered as the local forcing for the biennial monsoon cycle, and ENSO the remote effect. Copyright © 2010 Royal Meteorological Society
Blinded sample size reestimation with count data: Methods and applications in multiple sclerosis
Authors: Friede Tim , Schmidli Heinz
Published: February 2010

Sample size estimation in clinical trials depends critically on nuisance parameters, such as variances or overall event rates, which have to be guessed or estimated from previous studies in the planning phase of a trial. Blinded sample size reestimation estimates these nuisance parameters based on blinded data from the ongoing trial, and allows to adjust the sample size based on the acquired information. In the present paper, this methodology is developed for clinical trials with count data as the primary endpoint. In multiple sclerosis such endpoints are commonly used in phase 2 trials (lesion counts in magnetic resonance imaging (MRI)) and phase 3 trials (relapse counts). Sample size adjustment formulas are presented for both Poisson‐distributed data and for overdispersed Poisson‐distributed data. The latter arise from sometimes considerable between‐patient heterogeneity, which can be observed in particular in MRI lesion counts. The operation characteristics of the procedure are evaluated by simulations and recommendations on how to choose the size of the internal pilot study are given. The results suggest that blinded sample size reestimation for count data maintains the required power without an increase in the type I error. Copyright © 2010 John Wiley & Sons, Ltd.
Transforming Growth Factor-β and Notch Signaling Mediate Stem Cell Differentiation into Smooth Muscle Cells
Authors: Kurpinski Kyle , Lam Hayley , Chu Julia , Wang Aijun , Kim Ahra , Tsay Eric , Agrawal Smita , Schaffer David V. , Li Song
Published: February 2010

The differentiation of stem cells into smooth muscle cells (SMCs) plays an important role in vascular development and remodeling. In addition, stem cells represent a potential source of SMCs for regenerative medicine applications such as constructing vascular grafts. Previous studies have suggested that various biochemical factors, including transforming growth factor-β (TGF-β) and the Notch pathway, may play important roles in vascular differentiation. However, the interactions of these two signaling pathways in the differentiation of bone marrow mesenchymal stem cells (MSCs) have not been clearly defined. In this study, we profiled the gene expression in MSCs in response to TGF-β, and showed that TGF-β induced Notch ligand Jagged 1 (JAG1) and SMC markers, including smooth muscle α-actin (ACTA2), calponin 1 (CNN1), and myocardin (MYOCD), which were dependent on the activation of SMAD3 and Rho kinase. In addition, knocking down JAG1 expression partially blocked ACTA2 and CNN1 expression and completely blocked MYOCD expression, suggesting that JAG1 plays an important role in TGF-β-induced expression of SMC markers. On the other hand, the activation of Notch signaling induced the expression of SMC markers in MSCs and human embryonic stem cells (hESCs). Notch activation in hESCs also resulted in an increase of neural markers and a decrease of endothelial markers. These results suggest that Notch signaling mediates TGF-β regulation of MSC differentiation and that Notch signaling induces the differentiation of MSCs and hESCs into SMCs, which represents a novel mechanism involved in stem cell differentiation.
The impact of a classroom intervention on grade 10 students' argumentation skills, informal reasoning, and conceptual understanding of science
Authors: Venville Grady J. , Dawson Vaille M.
Published: February 2010

The literature provides confounding information with regard to questions about whether students in high school can engage in meaningful argumentation about socio‐scientific issues and whether this process improves their conceptual understanding of science. The purpose of this research was to explore the impact of classroom‐based argumentation on high school students' argumentation skills, informal reasoning, and conceptual understanding of genetics. The research was conducted as a case study in one school with an embedded quasi‐experimental design with two Grade 10 classes (n = 46) forming the argumentation group and two Grade 10 classes (n = 46) forming the comparison group. The teacher of the argumentation group participated in professional learning and explicitly taught argumentation skills to the students in his classes during one, 50‐minute lesson and involved them in whole‐class argumentation about socio‐scientific issues in a further two lessons. Data were generated through a detailed, written pre‐ and post‐instruction student survey. The findings showed that the argumentation group, but not the comparison group, improved significantly in the complexity and quality of their arguments and gave more explanations showing rational informal reasoning. Both groups improved significantly in their genetics understanding, but the improvement of the argumentation group was significantly better than the comparison group. The importance of the findings are that after only a short intervention of three lessons, improvements in the structure and complexity of students' arguments, the degree of rational informal reasoning, and students' conceptual understanding of science can occur. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 47: 952–977, 2010
Exploring identities to deepen understanding of urban high school students' sexual health decision‐making
Authors: Brotman Jennie S. , Mensah Felicia Moore , Lesko Nancy
Published: February 2010

Sexual health is a controversial science topic that has received little attention in the field of science education, despite its direct relevance to students' lives and communities. Moreover, research from other fields indicates that a great deal remains to be learned about how to make school learning about sexual health influence the real‐life choices of students. In order to provide a more nuanced understanding of young people's decision‐making, this study examines students' talk about sexual health decision‐making through the lens of identities. Qualitative, ethnographic research methods with twenty 12th grade students attending a New York City public school are used to illustrate how students take on multiple identities in relation to sexual health decision‐making. Further, the study illustrates how these identities are formed by various aspects of students' lives, such as school, family, relationships, and religion, and by societal discourses on topics such as gender, individual responsibility, and morality. The study argues that looking at sexual health decision‐making—and at decision‐making about other controversial science topics—as tied to students' identities provides a useful way for teachers and researchers to grasp the complexity of these decisions, as a step toward creating curriculum that influences them. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 47:742–762, 2010
Holzoberflächenmodifikation mittels Atmosphärendruckplasma
Authors: Avramidis Georg , Nothnick Evelyn , Wolkenhauer Arndt , Militz Holger , Viöl Wolfgang
Published: February 2010

Im vorliegenden Artikel werden plasmatechnische, analytische und anwendungsrelevante Aspekte der Plasmabehandlung von Holz und Holzwerkstoffen vorgestellt. Anhand von Oberflächenenergiebestimmungen und Adhäsionstests wird gezeigt, dass sich die Oberflächen von Holz und Holzwerkstoffen für spezifische Anwendungen verändern lassen. So können unter Verwendung eines Luftplasmas anwendungstechnisch interessante Oberflächeneigenschaften im Hinblick auf eine nachfolgende Beschichtung bzw. Verklebung gezielt generiert werden. Mit oberflächenenergetischen Untersuchungen von Holz und Holzwerkstoffen konnte nach einer Plasmabehandlung ein signifikant erhöhter polarer Anteil der Oberflächenenergie nachgewiesen werden. Rasterkraftmikroskopische Untersuchungen von Holzkompositen zeigen, dass eine Plasmabehandlung unter Verwendung von Umgebungsluft eine Abrasion und veränderte Oberflächenrauhigkeit bewirkt. Zug‐ und Schertests an plasmabehandelten beschichteten oder verklebten Holzwerkstoffen weisen eine deutlich erhöhte Haftfestigkeit auf.
El Niño and our future climate: where do we stand?
Authors: Vecchi Gabriel A. , Wittenberg Andrew T.
Published: February 2010

El Niño and La Niña comprise the dominant mode of tropical climate variability: the El Niño and Southern Oscillation (ENSO) phenomenon. ENSO variations influence climate, ecosystems, and societies around the globe. It is, therefore, of great interest to understand the character of past and future ENSO variations. In this brief review, we explore our current understanding of these issues. The amplitude and character of ENSO have been observed to exhibit substantial variations on timescales of decades to centuries; many of these changes over the past millennium resemble those that arise from internally generated climate variations in an unforced climate model. ENSO activity and characteristics have been found to depend on the state of the tropical Pacific climate system, which is expected to change in the 21st century in response to changes in radiative forcing (including increased greenhouse gases) and internal climate variability. However, the extent and character of the response of ENSO to increased in greenhouse gases are still a topic of considerable research, and given the results published to date, we cannot yet rule out possibilities of an increase, decrease, or no change in ENSO activity arising from increases in CO2. Yet we are fairly confident that ENSO variations will continue to occur and influence global climate in the coming decades and centuries. Changes in continental climate, however, could alter the remote impacts of El Niño and La Niña. Copyright © 2010 John Wiley & Sons, Ltd.

This article is categorized under:

Paleoclimates and Current Trends > Detection and Attribution
Speciation of antimony in polyethylene terephthalate bottles
Authors: Martin Ronald R. , Shotyk William S. , Naftel Steven J. , Ablett James M. , Northrup Paul
Published: February 2010

Antimony contamination has been reported in drinking water from polyethylene terephthalate (PET) bottles. Micro‐X‐ray fluorescence (XRF) analysis has been used to identify the distribution and chemical form of residual antimony used as a catalyst in the manufacture of PET bottles. The results are consistent with clusters of Sb(III) having dimensions of the order of tens of micrometers, clearly showing the ability of synchrotron radiation analyses to both map elemental distribution and determine oxidation state. Copyright © 2010 John Wiley & Sons, Ltd.
Tumor Protein p53‐Induced Nuclear Protein (TP53INP1) Expression in Medullary Thyroid Carcinoma: A Molecular Guide to the Optimal Extent of Surgery?
Authors: Taïeb D. , Giusiano S. , Sebag F. , Marcy M. , de Micco C. , Palazzo F. F. , Dusetti N. J. , Iovanna J. L. , Henry J. F. , Garcia S. , Taranger‐Charpin Colette
Published: February 2010

Background

Medullary thyroid cancer (MTC) is characterized by early regional lymph node metastasis, the presence of which represents a critical obstacle to cure. At present no molecular markers have been successfully integrated into the clinical care of sporadic MTC. The present study was designed to evaluate TP53INP1 expression in MTC and to assess its ability to guide the surgeon to the optimal extent of surgery performed with curative intent.

Methods

Thirty‐eight patients with sporadic MTC were evaluated. TP53INP1 immunoexpression was studied on embedded paraffin material and on cytological smears.

Results

TP53INP1 was expressed in normal C cells, in C‐cell hyperplasia, and in 57.9% of MTC. It was possible to identify two groups of MTC according to the proportion of TP53INP1 expressing tumor cells: group 1 from 0% to <50% and group 2 from 50% to 100% of positive cells. Patients with a decreased expression of TP53INP1 (group 1) had a lower rate of nodal metastasis (18.8% versus 63.4% in group 2; P = 0.009), with only minimal lymph node involvement per N1 patient (2.7% of positive lymph nodes versus 22.9%; P < 0.001) and better outcomes (100% of biochemical cure versus 55.5%; P < 0.001). Patients with distant metastases were only observed in group 2. Cytological samples exhibit similar results to their embedded counterparts.

Conclusions

TP53INP1 immunoexpression appears to be a clinical predictor of lymph node metastasis in MTC. The evaluation of TP53INP1 expression may guide the extent of lymph node dissection in the clinically node‐negative neck. These findings require prospective validation.
Outcome of Total Parathyroidectomy and Autotransplantation as Treatment of Secondary and Tertiary Hyperparathyroidism in Children and Adults
Authors: Kievit A. J. , Tinnemans J. G. M. , Idu M. M. , Groothoff J. W. , Surachno S. , Aronson D. C.
Published: February 2010

Background

Treatment safety and effectiveness of total parathyroidectomy and autotransplantation for secondary and tertiary hyperparathyroidism have been extensively proven in adults; the evidence for children, however, is scarce. Children and adolescents cannot simply be seen as young adults in the case of chronic kidney disease and hyperparathyroidism. The aim of this retrospective study was therefore, to evaluate whether parathyroidectomy with forearm autograft is as effective and safe in children and adolescents as in adults.

Methods

A group of 64 adults and 8 children and adolescents treated for secondary or tertiary hyperparathyroidism were retrieved from our database. The outcomes were compared on patient demographics, operation results, and blood parameters consisting of parathyroid hormone (PTH) and calcium levels. Our results were compared with all currently available articles on parathyroidectomy in children with secondary or tertiary hyperparathyroidism (n = 11).

Results

For adults, preoperative mean serum calcium was 2.67 ± 0.29 mmol/l and mean parathyroid hormone (PTH) level was 120 ± 86 pmol/l. For children, preoperative mean serum calcium was 2.62 ± 0.20 mmol/l and mean parathyroid hormone (PTH) level was 80 ± 38 pmol/l. Postoperative calcium and parathyroid hormone levels for adults dropped to 2.39 ± 0.23 mmol/l and 30 ± 53 pmol/l, respectively. Postoperative calcium and parathyroid hormone levels for children dropped to 2.41 ± 0.16 mmol/l and 26 ± 33 pmol/l, respectively. The effectiveness of parathyroidectomy with autotransplantation was 75% in children and 72% in adults. Thus, effectiveness did not differ significantly between children and adults.

Conclusions

Combining the results of our own study with a literature review on pediatric parathyroidectomy, we conclude that parathyroidectomy and forearm autograft is as effective a treatment for secondary and tertiary hyperparathyroidism in children and adolescents as it is in adults.
Clinical Significance of B7‐H1 and B7‐1 Expressions in Pancreatic Carcinoma
Authors: Wang Liancai , Ma Qingyong , Chen Xiangli , Guo Kun , Li Junhui , Zhang Min
Published: February 2010

Background

Cancer cells develop mechanisms to evade immune cells and achieve progression. Aberrant B7‐H1 and B7‐1 expressions may help pancreatic carcinoma (PC) cells escape immune attack; these molecules can be considered as prognostic markers for patients with PC who have undergone radical resection.

Methods

We recruited 81 patients who had undergone radical surgical resection for PC between 1999 and 2007. To investigate the prognostic factors, we evaluated the B7‐H1 and B7‐1 protein expressions in the tissue specimens of these 81 patients by immunohistochemistry and analyzed the clinical and pathological features of these specimens.

Results

B7‐H1 was expressed mainly in pancreatic islets, and no B7‐1 expression was detected in normal pancreatic tissues. B7‐H1 and B7‐1 expressions were higher in pancreatic carcinoma tissues than in normal pancreatic tissues (P < 0.05). B7‐H1 and B7‐1 significantly correlated with the pathological grade and tumor‐node‐metastasis (TNM) stage, respectively (P < 0.05). Furthermore, B7‐1‐negative or B7‐H1‐positive statuses were prognostic indicators of poor disease‐specific survival (P < 0.05), but only combined B7‐1/B7‐H1 expression retained the prognostic potential after adjusting by Cox proportional hazards regression models (P < 0.05).

Conclusions

Both B7‐H1 and B7‐1 are expressed in PC; these molecules are important markers for PC progression. Furthermore, combined B7‐1/B7‐H1 expression can serve as an independent prognostic marker for PC.
Different Sites and Prognoses of Gastrointestinal Stromal Tumors of the Stomach: Report of 187 Cases
Authors: Huang Hai , Liu Yan‐Xue , Zhan Zhong‐Li , Liang Han , Wang Pu , Ren Xiu‐Bao
Published: February 2010

Background

The stomach is the most common site of gastrointestinal stromal tumors (GISTs), but the clinical behavior of gastric GISTs at different sites is unclear. This study was designed to evaluate the clinicopathological (CP) parameters and influence of different gastric sites on outcome in patients with GIST.

Methods

The CP and follow‐up records of 187 patients with GIST who were treated at TianJin Medical University Cancer Institute & Hospital between January 1985 and December 2006 were reviewed. There were 97 men and 90 women (aged 17–88 (median, 56.5) years). CP factors were assessed for overall survival (OS) by using univariate and multivariate analysis.

Results

The numbers of cases of upper, middle, and lower third gastric GISTs were 69 (36.9%), 103 (55.1%), and 15 (8%), respectively. Sites of GISTs in the middle or upper stomach, tumor size, intermediate‐ or high‐risk groups, high mitotic count, and low resection status were associated with poor OS (p = 0.041, 0.046, 0.006, 0.000, 0.000, respectively) in a univariate analysis. In a multivariate analysis, tumor location in the upper and middle third of the stomach (p = 0.035), an intermediate or high risk (p = 0.01), and incomplete resection status (p = 0.006) were predictive of poor OS.

Conclusions

Patients in intermediate‐ and high‐risk groups had an unfavorable outcome. A complete resection is the most important treatment for survival. The location of GIST in the lower third of the stomach may be a favorable factor, and the significance of different tumor sites for prognosis of gastric GISTs needs to be further clarified.
The Antioxidant Functions of Tocopherol and Tocotrienol Homologues in Oils, Fats, and Food Systems
Authors: Seppanen Christine M. , Song Qinghua , Saari Csallany A.
Published: February 2010

This review paper is focused on the relative antioxidant activities of tocopherols and tocotrienols in oils and fats and certain food systems. α‐Tocopherol generally showed better antioxidant activity than γ‐tocopherol in fats and oils, but at higher concentrations γ‐tocopherol was found to be a more active antioxidant. The results of studies on the optimum antioxidant concentrations of tocopherols in oils and fats indicated that the optimal level for α‐tocopherol is usually lower than other tocopherols, meaning less α‐tocopherol is needed for maximum antioxidant protection. There are comparatively very few studies related to the antioxidant activities of tocotrienols in oils and fats. It has been stated that generally γ‐tocotrienol has higher antioxidant effect than α‐tocotrienol, and tocotrienols may be better antioxidants than their corresponding tocopherols in certain oils and fats systems. Studies on the antioxidant activity of various tocopherols in food systems are varied and cannot be uniformly evaluated because experiments have generally focused on different foods and used various methods for the detection of antioxidant activities. Depending on the food system, in certain cases tocopherols were better antioxidants than synthetic antioxidants such as butylhydroxy toluene (BHT) or butylhydroxy anisole (BHA). However, in certain other food systems the synthetic antioxidants were more effective to increase the shelf life and the stability of foods than those containing tocopherols.
The Validation of AORN Recommended Practices in Finnish Perioperative Nursing Documentation
Authors: Tiusanen Teija Susanna , Junttila Kristiina , Leinonen Tuija , Salanterä Sanna
Published: February 2010

In Finland, there are no common guidelines or recommended practices for perioperative documentation. Thus, perioperative nursing documentation varies from one operating department to another. To create minimum criteria for nursing documentation in Finland, we conducted an investigation in a university hospital district in 2006. Purposive sampling was used to invite experts in perioperative nursing documentation (N = 42) to serve as a Delphi panel. The final criteria are 120 items, 71% of which are based on the AORN standards and recommended practices. These criteria may be used to educate students and new perioperative personnel and to enhance the quality of nursing practice. To ensure relevance and usability, the criteria should be tested in various perioperative settings with a variety of surgical patients.