bluuebunny/crossref_metadata_2025_split huggingface dataset:
The seed cone Eathiestrobus gen. nov.: Fossil evidence for a Jurassic origin of Pinaceae
Authors: Rothwell Gar W. , Mapes Gene , Stockey Ruth A. , Hilton Jason 
Published: April 2012

• Premise of the study: Pinaceae and nonpinoid species are sister groups within the conifer clade as inferred from molecular systematic comparisons of living species and therefore should have comparable geological ages. However, the fossil record for the nonpinoid lineage of extant conifer families is Triassic, nearly 100 million years older than the oldest widely accepted Lower Cretaceous record for Pinaceae. An anatomically preserved fossil conifer seed cone described here extends the stratigraphic range of Pinaceae nearly 30 million years, thus reducing the apparent discrepancy between evidence from the fossil record and inferences from systematic studies of living species.• Methods: Material was prepared as serial thin sections by the cellulose acetate peel technique, mounted on microscope slides, and viewed and photographed using transmitted light.• Key results: A large cylindrical cone consisting of bract‐scale complexes that diverge from the cone axis in a helical phyllotaxis has bracts and scales that separate from each other in the midregion and are of equal length and of nearly equal width. The cone has two inverted and winged seeds that are attached to the adaxial surface of each cone scale and, thus, represents an early member of the Pinaceae.• Conclusions: Eathiestrobus mackenziei gen. et sp. nov. extends the fossil record for well‐documented members of the family Pinaceae from the Lower Cretaceous to the Kimmeridgian Stage of the Upper Jurassic. This species also clarifies the set of characters that are diagnostic for seed cones of Pinaceae and reveals possible plesiomorphic characters for seed cones of the family.
Serum Osteoprotegerin is Increased and Predicts Survival in Idiopathic Pulmonary Arterial Hypertension
Authors: Condliffe Robin , Pickworth Josephine A. , Hopkinson Kay , Walker Sara J. , Hameed Abdul G. , Suntharaligam Jay , Soon Elaine , Treacy Carmen , Pepke‐Zaba Joanna , Francis Sheila E. , Crossman David C. , Newman Christopher M. H. , Elliot Charles A. , Morton Allison C. , Morrell Nicholas W. , Kiely David G. , Lawrie Allan 
Published: April 2012

We previously reported that osteoprotegerin (OPG) is regulated by pathways associated with pulmonary arterial hypertension (PAH), and is present at elevated levels within pulmonary vascular lesions and sera from patients with idiopathic PAH (IPAH). Since OPG is a naturally secreted protein, we investigated the relationship between serum OPG and disease severity and outcome in patients with IPAH and animal models. OPG mRNA expression was measured in pulmonary artery smooth muscle cells (PASMC) from pulmonary arteries of patients with and without IPAH. Serum concentrations of OPG were measured in a retrospective and prospective group of patients. OPG levels were compared with phenotypic data and other putative PAH biomarkers. Prognostic significance was assessed and levels compared with healthy controls. Correlation of OPG and pulmonary vascular remodeling was also performed in rodent models of PAH. OPG mRNA was significantly increased 2‐fold in PASMC isolated from explanted PAH lungs compared with control. Serum OPG concentrations were markedly elevated in IPAH compared with controls. In Cohort 1 OPG levels significantly correlated with mean right atrial pressure and cardiac index, while in Cohort 2 significant correlations existed between age‐adjusted OPG levels and gas transfer. In both cohorts an OPG concentration above a ROC‐derived threshold of 4728 pg/ml predicted poorer survival. In two rodent models, OPG correlated with the degree of pulmonary vascular remodeling. OPG levels are significantly elevated in patients with idiopathic PAH and are of prognostic significance. The role of OPG as a potential biomarker and therapeutic target merits further investigation.
Three‐Dimensional Analysis of Right Ventricular Shape and Function in Pulmonary Hypertension
Authors: Leary Peter J. , Kurtz Christopher E. , Hough Catherine L. , Waiss Mary‐Pierre , Ralph David D. , Sheehan Florence H. 
Published: April 2012

Right ventricular (RV) failure is a key determinant of morbidity and mortality in pulmonary hypertension (PH). The present study aims to add to existing descriptions of RV structural and functional changes in PH through a comprehensive three‐dimensional (3D) shape analysis. We performed 3D echocardiography on 53 subjects with PH and 19 normal subjects. Twenty short‐axis slices from apex to tricuspid centroid were measured to characterize regional shape: apical angle, basal bulge, eccentricity, and area. Transverse shortening was assessed by fractional area change (FAC) in each short‐axis slice, longitudinal contraction was assessed by tricuspid annular plane systolic excursion (TAPSE) and global function by RV ejection fraction. Multivariate logistic analysis was used to compare the association of RV parameters with New York Heart Association (NYHA) class. Compared to normal, RV function in PH is characterized by decreased stroke volume index (SVi), fractional area change and ejection fraction. Increased eccentricity, apical rounding and bulging at the base characterize the shape of the RV in PH. Increased SVi, ejection fraction and mid‐ventricular FAC were associated with less severe NYHA class in adjusted analyses. The RV in idiopathic PH (iPAH) was observed to have a larger end‐diastolic volume and decreased function compared with connective tissue disease associated PH (ctd‐PH). This work describes increased eccentricity and decreased systolic function in subjects with PH. Functional parameters were associated with NYHA class and heterogeneity in the phenotype was noted between subjects with iPAH and ctd‐PH.
Inhaled Epoprostenol Therapy for Pulmonary Hypertension: Improves Oxygenation Index More Consistently in Neonates than in Older Children
Authors: Brown Anna T. , Gillespie Jennifer V. , Miquel‐Verges Franscesca , Holmes Kathryn , Ravekes William , Spevak Philip , Brady Ken , Easley R. Blaine , Golden W. Christopher , McNamara LeAnn , Veltri Michael A. , Lehmann Christoph U. , McMillan Kristen Nelson , Schwartz Jamie M. , Romer Lewis H. 
Published: April 2012

The purpose of this study was to determine the efficacy of inhaled epoprostenol for treatment of acute pulmonary hypertension (PH) in pediatric patients and to formulate a plan for a prospective, randomized study of pulmonary vasodilator therapy in this population. Inhaled epoprostenol is an effective treatment for pediatric PH. A retrospective chart review was conducted of all pediatric patients who received inhaled epoprostenol at a tertiary care hospital between October 2005 and August 2007. The study population was restricted to all patients under 18 years of age who received inhaled epoprostenol for greater than 1 hour and had available data for oxygenation index (OI) calculation. Arterial blood gas values and ventilator settings were collected immediately prior to epoprostenol initiation, and during epoprostenol therapy (as close to 12 hours after initiation as possible). Echocardiograms were reviewed during two time frames: Within 48 hours prior to therapy initiation and within 96 hours after initiation. Of the 20 patients in the study population, 13 were neonates, and the mean OI for these patients improved during epoprostenol administration (mean OI before and during therapy was 25.6±16.3 and 14.5±13.6, respectively, P=0.02). Mean OI for the seven patients greater than 30 days of age was not significantly different during treatment (mean OI before and during therapy was 29.6±15.0 and 25.6±17.8, P=0.56). Improvement in echocardiographic findings (evidence of decreased right‐sided pressures or improved right ventricular function) was demonstrated in 20% of all patients. Inhaled epoprostenol is an effective therapy for the treatment of selected pediatric patients with acute PH. Neonates may benefit more consistently from this therapy than older infants and children. A randomized controlled trial is needed to discern the optimal role for inhaled prostanoids in the treatment of acute PH in childhood.
The WHO Classification of Pulmonary Hypertension: A Case‐Based Imaging Compendium
Authors: Ryan John J. , Thenappan Thenappan , Luo Nancy , Ha Thanh , Patel Amit R. , Rich Stuart , Archer Stephen L. 
Published: April 2012

Pulmonary hypertension (PH) is defined as a resting mean pulmonary artery pressure greater than 25 mmHg. The World Health Organization (WHO) classifies PH into five categories. The WHO nomenclature assumes shared histology and pathophysiology within categories and implies category‐specific treatment. Imaging of the heart and pulmonary vasculature is critical to assigning a patient's PH syndrome to the correct WHO category and is also important in predicting outcomes. Imaging studies often reveal that the etiology of PH in a patient reflects contributions from several categories. Overlap between Categories 2 and 3 (left heart disease and lung disease) is particularly common, reflecting shared risk factors. Correct classification of PH patients requires the combination of standard imaging (chest roentgenograms, ventilation‐perfusion scans, echocardiography, and the 12‐lead electrocardiogram) and advanced imaging (computed tomography, cardiac magnetic resonance imaging, and positron emission tomography). Despite the value of imaging, cardiac catheterization remains the gold standard for quantification of hemodynamics and is required before initiation of PH‐specific therapy. These cases illustrate the use of imaging in classifying patients into WHO PH Categories 1–5.
Investigation of the properties of conductive hydrogel composite containing Zn particles
Authors: Golikand Ahmad Nozad , Didehban Khadijeh , Rahimi Rahmatollah 
Published: April 2012

AbstractIn this work, the conductive hydrogel composites containing Zn particle synthesized and their electrical and thermal properties were investigated. Polyacrylamide/Zn composites were synthesized by free radical polymerization in aqueous solution. The effect of preparation conditions such as the influence of crosslinker amount, initiator amount, Zn amount, and water absorbency on electrical conductivity of hydrogel was investigated. The effect of preparation conditions on thermal properties has been characterized using thermogravimetric analysis (TGA) method. The structures of metal‐composites were evaluated by FTIR and scanning electron microscopy (SEM) methods. SEM revealed a more uniform pore size when Zn particles were used when compared with pure polyacrylamide. TGA curves showed that both hydrogels were stable upto 600°C. The Zn/polyacrylamide hydrogels have a good conductivity of 4.30 mS cm−1. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Irradiation‐induced grafting of poly(vinylidene fluoride)‐graft‐poly(styrene sulfonic acid) for the preparation of planar and tube‐shaped air‐drying membranes
Authors: Cohen Eyal , Ophir Amos 
Published: April 2012

AbstractA novel air‐drying membrane was developed and investigated as an alternative for planar and tube‐shaped drying membranes composed of Nafion®. The new membrane is based on poly(vinylidene fluoride) (PVDF) polymer types grafted with polystyrene sulfonic acid. Modification of the PVDF membrane by chemical grafting was initiated via γ‐irradiation of pre‐made film and tube‐shaped samples. The grafting was conducted while the pre‐irradiated PVDF samples were immersed in styrene monomer solution. Three unique characterization methods were introduced to evaluate the ion exchange and barrier functions of the membrane. This investigation focuses on optimizing the degree of grafting yield, and subsequently the control of the membrane's overall functional performances, through (1) monitoring the PVDF's degree of crystallinity and (2) monitoring the styrene monomer solution temperature, respectively. Different levels of crystallinity were achieved by melt blending the PVDF‐copolymer with PVDF‐homopolymer, in various mixing ratios. Another variable examined in this investigation was the introduction of an ionic complex on the sulfonic acid end groups, and its effect on the membrane functional performance was studied. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Study of two chitosan derivatives phosphorylated at hydroxyl or amino groups for application as flocculants
Authors: Zhao Di , Xu JianFeng , Wang Lu , Du JianJia , Dong KeDong , Wang CaiFei , Liu XiangDong 
Published: April 2012

AbstractTwo phosphorylated chitosan derivatives with a similar degree of substitution of about 0.5 were synthesized via either the esterification of chitosan's hydroxyl groups by P2O5 in methanesulfonic acid or the selective incorporation of methylene phosphonic groups on chitosan's amino groups by formaldehyde/H3PO3 in water. The performances of the resulting O‐phosphorylated chitosan (OPC) and N‐methylene phosphonic chitosan (NMPC) as amphoteric flocculants were assessed in comparison with that of unmodified chitosan. In turbidity removal experiments using kaolin suspensions in water, OPC removed about 90% turbidity, but NMPC only removed 60%. The lower flocculation efficiency of NMPC was attributed to the decreased acid strength of the N‐methylene phosphate groups in NMPC. These results revealed that the acidity of the phosphate groups introduced in the modified chitosans is an important factor with regard to the flocculation efficiency, and consequently that O‐phosphorylation is more suitable than N‐phosphorylation for preparing chitosan‐based amphoteric flocculants. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Bacterial cellulose–poly(vinyl alcohol) nanocomposite hydrogels prepared by chemical crosslinking
Authors: Yang Liang , Zhang Hong‐Yu , Yang Qun , Lu Da‐nian 
Published: April 2012

AbstractThe bacterial cellulose–poly(vinyl alcohol) (BC/PVA) nanocomposite hydrogels using BC as the reinforcement and PVA as the matrix materials were formed in coagulating bath and crosslinked with formaldehyde, and characterized by attenuated total reflection Fourier transform infrared spectroscopy, mechanical properties tests, thermogravimetric analysis, and scanning electron microscope analysis. It was known that the chemical cross‐linked BC/PVA nanocomposite hydrogels exhibited some promising characteristics, such as appropriate mechanical strength and excellent thermal properties. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Environment friendly UV‐curable resins from palm stearin alkyds
Authors: Ang Desmond Teck Chye , Gan Seng Neon 
Published: April 2012

AbstractNon‐self‐drying palm stearin alkyds were converted into UV‐curable resins via fumarization and maleinization. The maleated alkyds (AlkM) and fumarized alkyds (AlkF) were characterized by 1H‐NMR and FTIR before they were formulated into UV‐curable coatings, with methyl methacrylate as the active diluents, and benzophenone as UV photoinitiator. The film properties, which include the film hardness, adhesion, water and alkali resistance, and thermal stability, of the two series of alkyd coatings were compared. In both series, alkyds with high amount of CHCH could be cured with UV within short time to produce coatings with good film properties. Although both approaches, fumarization and maleinization, serve the same purpose to increase the level of unsaturation in the alkyd, it was found that coatings produced from the two series of alkyds have different UV curability and film properties. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Generation and characterization of a Notch1 signaling‐specific reporter mouse line
Authors: Smith Emma , Claudinot Stéphanie , Lehal Rajwinder , Pellegrinet Luca , Barrandon Yann , Radtke Freddy 
Published: April 2012

AbstractSignaling through the Notch1 receptor is essential for the control of numerous developmental processes during embryonic life as well as in adult tissue homeostasis and disease. Since the outcome of Notch1 signaling is highly context‐dependent, and its precise physiological and pathological role in many organs is unclear, it is of great interest to localize and identify the cells that receive active Notch1 signals in vivo. Here, we report the generation and characterization of a BAC‐transgenic mouse line, N1‐Gal4VP16, that when crossed to a Gal4‐responsive reporter mouse line allowed the identification of cells undergoing active Notch1 signaling in vivo. Analysis of embryonic and adult N1‐Gal4VP16 mice demonstrated that the activation pattern of the transgene coincides with previously observed activation patterns of the endogenous Notch1 receptor. Thus, this novel reporter mouse line provides a unique tool to specifically investigate the spatial and temporal aspects of Notch1 signaling in vivo. genesis 50:700–710, 2012. © 2012 Wiley Periodicals, Inc.
Predicting the early invasiveness of nasopharyngeal mucosal neoplasia after radiotherapy by narrow‐band imaging: A pilot study
Authors: Lin Yen‐Chun , Wang Wen‐Hung , Tsai Wan‐Chi , Chen Chih‐Cheng , Chen Wen‐Cheng , Lee Kam‐Fai 
Published: April 2012

AbstractBackgroundThis study evaluated the correlation between the histologic findings of nasopharyngeal mucosal neoplasias after radiotherapy and narrow‐band imaging (NBI) endoscopic findings.MethodsOne hundred six patients were enrolled. All patients underwent conventional white‐light endoscopic examinations of the nasopharynx, which were followed by NBI endoscopy. Biopsy specimens were obtained if scattered brown‐spotted lesions were identified.ResultsWe identified 22 patients with brown‐spotted lesions by NBI endoscopy. Histopathologic study confirmed that 4 lesions were neoplastic, including 2 dysplastic lesions and 2 carcinomatous lesions. According to pathologic examinations, the thickness of the epithelium in carcinomatous, dysplastic, and nonneoplastic lesions were (mean ± SD) 0.85 ± 0.21 mm, 0.45 ± 0.21 mm, and 0.35 ± 0.07 mm, respectively. The epithelial thickness of carcinomatous and dysplastic lesions was significantly thicker than that of nonneoplastic lesions (p < .001 and p = .026, respectively). According to the NBI endoscopic examinations, the epithelial thickness of the brown‐spotted lesions with irregular borders was significantly thicker than those lesions with tailed/round borders (0.48 ± 0.24 mm vs 0.26 ± 0.07 mm, p = .009). Visualization by NBI corresponded to the histopathologic findings; the prevalence of neoplastic lesions with tailed/round borders and irregular borders was 0% (0/13) and 44.4% (4/9), respectively (p = .017).ConclusionsThis study demonstrates that lesions with an irregular pattern tend to be neoplastic lesions. Irregularities observed under NBI are important pathologic indicators of the early invasiveness of nasopharyngeal mucosal neoplasia after radiotherapy. This result warrants further inquiry to confirm its accuracy. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
BRAFV600E mutation in fine‐needle aspiration aspirates: Association with poorer prognostic factors in larger papillary thyroid carcinomas
Authors: Lee Ji In , Jang Hye Won , Kim Sun Wook , Kim Jong–Won , Oh Young Lyun , Chung Jae Hoon 
Published: April 2012

AbstractBackgroundRecent studies have shown that BRAFV600E mutation is associated with poor prognostic factors in papillary thyroid carcinoma (PTC). However, there are no studies about the association of the BRAFV600E mutation with poor prognostic factors according to tumor size in PTC.MethodsWe investigated the prevalence of the BRAFV600E mutation and its association with prognostic factors according to tumor size of PTC. BRAFV600E mutation status was assessed in thyroid fine‐needle aspiration (FNA) specimens from 605 patients before thyroidectomy for PTC, and its association with postoperative clinicopathologic factors was evaluated.ResultsThe overall prevalence of the BRAFV600E mutation was 67%, and larger tumors more often had the BRAFV600E mutation (p for trend < .05). The BRAFV600E mutation was significantly associated with male sex, tumor size, extrathyroidal invasion, nodal metastasis, and advanced tumor stage (p < .05). There was a significant size‐dependent relationship between the presence of the BRAFV600E mutation and extrathyroidal invasion, nodal metastasis, and advanced tumor stage (p for trend < .05).ConclusionThe prevalence of the BRAFV600E mutation increased with increased tumor size. Preoperative FNA‐detected BRAFV600E mutation was associated with poor prognostic factors, and the association was stronger in larger tumors. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Rate constants calculation of hydrogen abstraction reactions CH3CHBr + HBr and CH3CBr2 + HBr
Authors: Wang Li , Zhao Jianxiang , He Hongqing , Zhang Jinglai 
Published: April 2012

AbstractDual‐level direct dynamics method is used to study the kinetic properties of the hydrogen abstraction reactions of CH3CHBr + HBr → CH3CH2Br + Br (R1) and CH3CBr2 + HBr → CH3CHBr2 + Br (R2). Optimized geometries and frequencies of all the stationary points and extra points along the minimum‐energy path are obtained at the MPW1K/6‐311+G(d,p), MPW1K/ma‐TZVP, and BMK/6‐311+G(d,p) levels. Two complexes with energies less than that of the reactants are located in the entrance of each reaction at the MPW1K/6‐311+G(d,p) and MPW1K/ma‐TZVP levels, respectively. The energy profiles are further refined with the interpolated single‐point energies method at the G2M(RCC5)//MPW1K/6‐311+G(d,p) level of theory. By the improved canonical variational transition‐state theory with the small‐curvature tunneling correction (SCT), the rate constants are evaluated over a wide temperature range of 200–2000 K. Our calculations have shown that the radical reactivity decreases from CH3CHBr to CH3CBr2. Finally, the total rate constants are fitted by two modified Arrhenius expression. © 2012 Wiley Periodicals, Inc.
Magnetic, kinetic, and optical properties of new high‐pressure phases in the system Cr–GaSb: Ab initio density functional theory study
Authors: Kulatov Erkin , Magnitskaya Maria , Uspenskii Yurii , Popova Svetlana , Brazhkin Vadim , Maksimov Evgenii 
Published: April 2012

AbstractThe structural, transport, magnetic, and optical properties of high‐pressure‐synthesized metastable compounds CrGaSb and CrGa2Sb2 are calculated from first principles. In addition to theoretical results, new X‐ray structural measurements of CrGa2Sb2 up to 9 GPa are reported. Both high‐pressure phases CrGaSb and CrGa2Sb2 are found to be at the edge between metal and semiconductor, which implies that the standard density functional theory predictions may be misleading. To clarify the situation, a study is conducted whether the results depend significantly on the approximation used for the exchange–correlation potential. A possible effect of slight nonstoichiometry found in the CrGa2Sb2 samples is also investigated. The calculation results agree with most available experimental data and are internally consistent, which provides the assurance that, as a whole, they give a reliable picture of electronic properties in CrGaSb and CrGa2Sb2. © 2012 Wiley Periodicals, Inc.
Theoretical study on the reaction mechanism of formation of 3,5‐diacetyl‐1,4‐dihydrolutidine
Authors: Teramae Hiroyuki , Y. Maruo Yasuko 
Published: April 2012

AbstractWe have studied the reaction path of the formation of 3,5‐diacetyl‐1,4‐dihydrolutidine (DL1), 3,5‐dibenzoyl‐1,4‐dihydro‐2,6‐dimethylpyridine, and 2,6‐dibenzoyl‐1,4‐dihydro‐3,5‐dimethylpyridine with the ab initio molecular orbital method at HF/3‐21G and HF/6‐31G(d,p) levels. For DL1, we also calculated at MP2/6‐31G(d,p) level. The barrier heights of H2O elimination elementary reactions are about 50–60 kcal/mol and quite high in the gas phase, however, this is well agreed with the experimental results that the reaction proceeds in aqueous solutions. © 2012 Wiley Periodicals, Inc.