bluuebunny/crossref_metadata_2025_split huggingface dataset:
1,3‐dipolar cycloaddition reactions of 2‐substituted azomethine N‐oxides with N‐benzyl maleimides leading to the synthesis of stereoisomers
Authors: Badru Rahul , Shah Sakshi , Singh Baldev 
Published: December 2011

AbstractThe azomethine N‐oxides (1) on reacting with N‐benzylmaleimide (2) provide a mixture of stereoisomers 2,3‐diphenyl‐5‐benzyl‐4H‐2,3,3a,5,6,6a‐hexahydropyrrolo[3,4‐d]isoxazole‐4,6–dione derivatives (3) in good yields. These isomers have been assigned cis and trans configurations (3‐A and 3‐B) with respect to proton C3‐H on the azomethinic carbon on the basis of their PMR and H‐NMR COSY data. The ratio between cis and trans isomers has been found to be dependent on substituents present at ortho position of C‐phenyl aldehydic moiety. The salient feature of these 1,3‐dipolar cycloaddition reactions lies in that the benzylic protons on N‐benzyl moiety suffer gem coupling, indicating magnetic nonequivalence. J. Heterocyclic Chem.,, (2012).
Determination of the volatiles from tobacco by capillary gas chromatography with atomic emission detection and mass spectrometry
Authors: Li Gang , Wu Da , Wang Ye , Xie Wenyan , Zhang Xiangmin , Liu Baizhan 
Published: December 2011

AbstractA new gas chromatograph‐atomic emission detector (GC‐AED) coupled with Deans switching technique for analyzing volatiles from tobaccos were developed. The detector operating parameters (reagent gas pressure and make‐up gas flow rate) were optimized. The detection limits for the elements carbon (193 nm), hydrogen (486 nm) and oxygen (171 nm) ranged 0.05–0.2, 0.05–0.3 and 1–11 ng, respectively, depending on the compound. The sensitivity and linearity for the elements carbon (193 nm), hydrogen (486 nm) and oxygen (171 nm) decreased in the order O>H>C. Calibration curves were obtained by plotting peak area versus concentration, and the correlation coefficients relating to linearity were at least 0.9359. Elemental response factors measured on these channels, relative to the carbon 193‐nm channel, were hydrogen, 0.38–0.48 (mean %RSD=5.64), and oxygen, 0.085–0.128 (mean %RSD=14.9). The evaluation was also done for the new technique and for an established GC‐MS technique for the same real samples. The results of GC‐AED and GC‐MS showed that there was a relatively good agreement between the two sets of data.
Detection of L‐phenylalanine using molecularly imprinted solid‐phase extraction and flow injection electrochemiluminescence
Authors: Lu Juanjuan , Ge Shenguang , Wan Fuwei , Yu Jinghua 
Published: December 2011

AbstractA novel flow injection electrochemiluminescence method combined with molecularly imprinted solid‐phase extraction was developed for the determination of L‐phenylalanine, in which ${\rm{Ru(bpy}})_3^{2 + }$ was used as the luminophor and indium tin oxide glass was modified as the working electrode. Molecularly imprinted polymers, synthesized by self‐assembly with functional monomer and crossing linker, were used for the selective extraction of L‐phenylalanine. In order to overcome the drawbacks of traditional electrochemiluminescence cells such as high IR drop, high over‐potential and so on, a novel electrochemiluminescence cell was developed. The enhanced electrochemiluminescence intensity was linearly related with the concentration of L‐phenylalanine in the range from 1.0×10−7 to 5.0×10−5 g/mL with a detection limit of 2.59×10−8 g/mL. The relative standard deviation for the determination of 1.0×10−6 g/mL L‐phenylalanine was 1.2% (n=11). The method showed higher sensitivity and good repeatability, and was successfully applied for the determination of L‐phenylalanine in egg white, chicken and serum samples. A possible mechanism for the enhanced electrochemiluminescence response on indium tin oxide glass is proposed.
The definition of the V zone for the safety space of functional surgery of the tongue
Authors: Hou Tiening , Shao Jinyan , Fang Songhua 
Published: December 2011

AbstractObjectives/Hypothesis:To define safety space for functional surgery of the tongue.Study Design:Prospective nonrandomized study.Methods:Computed tomographic angiography of the lingual artery was performed in 107 in‐patients with obstructive sleep apnea syndrome and 17 controls. The safety space was ascertained according to the course of lingual artery.Results:The course of the lingual artery, termed the Big Dipper bowl of the tongue, was similar in each group. The tissue above the lingual artery and the vacuity of the hypoglossal/lingual artery neurovascular bundle (HLNVB) formed a three‐dimensional structure. The anterior part was named the V prozone. Its anterior border was the tangent plane of the deep lingual artery, its posterior border the circumvallate papilla, its width the interval of bilateral margins at the corresponding parts of the tongue, and its height the level of the middle lingual frenulum. The posterior portion between the bilateral dorsal arteries in the tongue base was named the V postzone. Its width was 31.42 ± 3.82 mm when the tongue was in a resting position, and its height was the distance from the foramen cecum to the bottom of the epiglottic vallecula. The inferior part under the intrinsic lingual muscles was named the hypoglossal floor. It is a relatively restricted surgery zone.Conclusions:The V zone of the tongue without HLNVB travelling provides enough of safety space for functional surgery on the tongue.Laryngoscope, 122:66–70, 2012
Standardized letter of recommendation for pediatric fellowship selection
Authors: Prager Jeremy D. , Perkins Jonathan N. , McFann Kim , Myer Charles M. , Pensak Myles L. , Chan Kenny H. 
Published: December 2011

AbstractObjectives/Hypothesis:To develop a pediatric otolaryngology fellowship selection standardized letter of recommendation (SLOR).Study Design:SLOR and narrative letter of recommendation (NLOR) comparison study.Methods:An SLOR was created to investigate qualities desired in fellows using five content‐based categories: writer background, comparison of the applicant to contemporaries and predecessors, applicant's qualifications for pediatric otolaryngology, a global assessment of the applicant, and a summary statement about the applicant. In phase I, the SLORs were completed, including writing time, by the applicant's pediatric otolaryngology chief. In phase II, letters were ranked on Likert‐type scales for the content‐based categories, reviewer's overall ranking, and ease of review by six otolaryngologists. Reviewers recorded time needed to review each letter.Results:Nineteen SLORs (73%) were collected. Mean writing time was 8.84 ± 3.87 minutes. Interrater reliability was higher on the SLORs in the content‐based sections and the overall ranking. Ranking times were lower on the SLORs. Mean and median rankings were higher on the SLORs for writer background, comparison of the applicant to contemporaries and predecessors, applicant's qualifications for pediatric otolaryngology, and ease of review; mean global assessment of the applicant, summary statement about the applicant, and overall rankings were lower on the SLORs.Conclusions:To our knowledge, this is the first inquiry using an SLOR developed for otolaryngology. SLORs are an alternative to NLORs for fellowship selection that offers improved reliability and efficiency. Further investigation using SLORs in otolaryngology residency selection is merited.
Methods of detailed thermal fatigue evaluation of nuclear power plant components
Authors: Rudolph J. , Bergholz S. , Willuweit A. , Vormwald M. , Bauerbach K. 
Published: December 2011

AbstractThe fatigue check of components has to be considered as an essential module of the safety concept as well as the ageing and lifetime management of nuclear power plants. It is based on special safety requirements in the design phase as well as in the framework of the ageing and lifetime management. Considerable efforts of load identification (fatigue monitoring) as well as the strict code conformity are characteristic features. The predominance of thermal cyclic loadings as well as relevant stress/strain amplitudes in the low cycle fatigue regime (LCF) are peculiarities compared to other technical domains. The code based fatigue concept is explained in the first part of the contribution. Furthermore, potentials for the quantification of existing margins are shown. On this, a new approach of mechanistic simulation of the thermal cyclic fatigue process based on short crack fracture mechanics is described in detail in the second part.
Prospective high‐resolution respiratory‐resolved whole‐heart MRI for image‐guided cardiovascular interventions
Authors: Kolbitsch Christoph , Prieto Claudia , Buerger Christian , Harrison James , Razavi Reza , Smink Jouke , Schaeffter Tobias 
Published: December 2011

AbstractCardiovascular diseases, including arrhythmias and heart failure, are commonly treated with percutaneous procedures guided by X‐ray fluoroscopy. The visualization of the targeted structures can be enhanced using preacquired respiratory‐resolved anatomic data (dynamic roadmap), which is displayed as an overlay onto X‐ray fluoroscopy images. This article demonstrates how dynamic roadmaps using an affine motion model can be obtained from one respiratory‐resolved three‐dimensional whole‐heart acquisition using the previously introduced Radial Phase Encoding‐Phase Ordering with Automatic Window Selection method. Respiratory motion in different regions of the heart was analyzed in 10 volunteers, and it was shown that the use of dynamic roadmaps can reduce misalignment errors from more than 10 down to less than 1.5 mm. Furthermore, the results suggest that reliable motion information can be obtained from highly undersampled images due to the advantageous undersampling properties of the radial phase encoding trajectory. Finally, results of a three‐dimensional dynamic roadmap obtained from a patient before catheter ablation for atrial fibrillation treatment are presented. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Utilizing echo‐shifts in k‐space for generation of positive contrast in areas with marked susceptibility alterations
Authors: Eibofner Frank , Steidle Günter , Kehlbach Rainer , Bantleon Rüdiger , Schick Fritz 
Published: December 2011

AbstractA technique for generation of positive contrast near susceptibility alterations utilizing echo‐shifts in k‐space is introduced, based on altered Larmor‐frequencies and resulting phase‐shifts accumulating during the echo‐time at the site of local magnetic field gradients. 3D gradient‐echo raw‐data is acquired and weighted with an inverse Hanning filter. The filter partly suppresses central raw‐data points, while maintaining outer areas. Reconstruction of the filtered raw‐data results in images where pixels with apparent magnetic field gradients are highlighted against homogeneous pixels. Further processing steps are introduced to remove remaining intensities in the homogeneous parts of the filtered image. Feasibility is shown by an agar phantom containing magnetically labeled cells, with concentrations of 25, 50, 100, and 250 cells/μL, and by images of the human head. The technique allows detection of echo‐shifted pixels with automatic suppression of magnetically homogeneous parts while keeping post‐processing time short. Fewer than four labeled cells per pixel were clearly displayed with positive contrast. Application to the human head shows bright veins and complete suppression of homogeneous regions. The presented technique has high potential for specific detection of low concentrations of labeled cells or susceptibility altered regions in vivo with positive contrast, whereas areas with low spin density are not highlighted. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Activation of Akt is associated with poor prognosis and chemotherapeutic resistance in pediatric B‐precursor acute lymphoblastic leukemia
Authors: Morishita Naoto , Tsukahara Hirokazu , Chayama Kosuke , Ishida Toshiaki , Washio Kana , Miyamura Takako , Yamashita Nobuko , Oda Megumi , Morishima Tsuneo 
Published: December 2011

AbstractBackgroundActivation of the phosphoinositide 3‐kinase (PI3K)/Akt pathway, a pro‐survival pathway, plays important roles in tumor cell growth. However, the role of Akt in the pathogenesis of pediatric B‐precursor acute lymphoblastic leukemia (B‐pre ALL) remains to be clarified. This study was undertaken to explore the clinical relevance and molecular mechanisms underlying the activation of Akt (i.e., phosphorylated Akt, P‐Akt) in pediatric B‐pre ALL.ProcedureWe evaluated the activation status of Akt in bone marrow samples from 21 children with newly diagnosed B‐pre ALL and correlated the expression level of P‐Akt with clinicopathologic and prognostic features. Additionally, we transfected the myristoylated Akt cDNA into the B‐pre ALL cell line, Nalm‐6, and examined the effect, in vitro, of Akt activation on the response to antitumor drugs.ResultsP‐Akt expression in B‐pre ALL blast cells at diagnosis was associated significantly with poor response to induction chemotherapy including prednisolone, dexamethasone, vincristine, and adriamycin in B‐pre ALL patients. Both overall survival and relapse‐free survival in patients with P‐Akt expression were reduced significantly more than in patients without P‐Akt expression. Activation of Akt reduced the extent of apoptosis induced by the antitumor drugs in Nalm‐6 listed above. Activation of Akt did not induce expression of P‐glycoprotein, a drug transporter that is capable of conferring multidrug resistance.ConclusionThese results support the contention that Akt activation is a mechanism of chemotherapeutic resistance in B‐pre ALL and suggest that Akt can be a therapeutic target for the treatment of relapsed or refractory pediatric B‐pre ALL. Pediatr Blood Cancer 2012; 59: 83–89. © 2011 Wiley Periodicals, Inc.
Long‐term outcome of hypothalamic pituitary tumors in Langerhans cell histiocytosis
Authors: Fahrner Bernhard , Prosch Helmut , Minkov Milen , Krischmann Martha , Gadner Helmut , Prayer Daniela , Grois Nicole 
Published: December 2011

AbstractBackgroundHypothalamic‐pituitary (HP) disease is the most common CNS manifestation of Langerhans cell histiocytosis (LCH) frequently leading to diabetes insipidus (DI) and anterior pituitary hormone deficiencies (APD). On MRI, loss of the normal posterior pituitary signal and thickening of the pituitary stalk have been described, as well as neurodegenerative signal changes associated with neuropsychological disabilities in some patients. The influence of therapy on the long‐term course of HP tumors and neurodegeneration (ND) is not well‐understood.ProcedureIn this retrospective survey we focused on patients with LCH and HP disease with clinical and MRI data available at diagnosis of HP disease and at least three follow up investigations. We collected clinical and MRI follow‐up information for central review and analysis.ResultsWe identified 22 patients with HP tumors (HPT) registered at the LCH study center. Many different treatment regimens were applied for variable periods, with more than one regimen in most patients. Regression of the tumor was seen in the majority, but all patients had APD or ND on MRI at last follow up. In none of the patients APD and ND regressed or resolved. A deterioration of radiological ND was noted in 17 patients leading to overt clinical neuropsychological impairment in five.ConclusionsPatients with HPT appear to be at high risk to develop permanent neuroendocrine consequences. Coordinated studies for patients with LCH and HP disease including thorough MRI monitoring and neuropsychological tests are needed. Pediatr Blood Cancer 2012; 58: 606–610. © 2011 Wiley Periodicals, Inc.
Design and seismic response of tall chevron panel buckling‐restrained braced steel frames
Authors: Ding Yukun , Zhang Yaochun 
Published: December 2011

SUMMARYThe numerical analysis of the seismic performance for tall chevron panel buckling‐restrained braced steel frames (PBRBFs) under small and strong earthquake excitations has been carried out to investigate a capacity design procedure for chevron PBRBFs and to examine the effects of axial strength distribution of braces along the height of buildings, vertical supports of braces for the braced beams and the overstrength of braces on the seismic response of PBRBFs. It revealed that the chevron braces that remained elastic can actually provide the vertical supports for the braced beams. Under severe earthquake excitations, the vertical supports deteriorated greatly after braces yielding. The PBRBFs designed by omitting vertical supports of braces for the braced beams and considering the overstrength of braces exhibited superior performance with smaller plastic deformations for braced beams and reduction in ductility demands for panel buckling‐restrained braces (PBRBs) as compared with the others. The distribution of yielding for PBRBs in 10‐story buildings verified that the participation from the higher modes is not very remarkable and that the capacity design based on the first‐mode response can be considered for multistory PBRBFs. Moreover, on the basis of the analysis results of the 30‐story PBRBF, the participation of the higher modes should be taken into account for high‐rise PBRBFs. Copyright © 2011 John Wiley & Sons, Ltd.
Isolation and Characterization of CH3OC(O)OOC(O)F from the Reaction CH3OH + FC(O)OOC(O)F
Authors: Berasategui Matias , Burgos Paci Maximiliano A. , Argüello Gustavo A. 
Published: December 2011

AbstractThe synthesis of CH3OC(O)OOC(O)F is accomplished by the thermal reaction between CH3OH and FC(O)OOC(O)F at room temperature. The new peroxide is obtained in pure form after repeated trap‐to‐trap condensation and it is characterized by NMR and IR spectroscopy and mass spectrometry. Geometrical parameters were studied by ab initio methods [B3LYP/6‐31++G(d, p)]. CH3OC(O)OOC(O)F is stable for a few hours at room temperature, and it decomposes into CO2, CO, HF, HC(O)OH, and CH2O.The boiling point is extrapolated to 366.5 K from the vapor pressure curve log p = 8.623–2061/T (p /mbar, T /K). The mechanisms for both the formation and thermal decomposition of CH3OC(O)OOC(O)F are discussed, and some physicochemical properties are compared with those of related compounds.
Viscous Marangoni propulsion
Authors: Lauga Eric , Davis Anthony M. J. 
Published: December 2011

AbstractMarangoni propulsion is a form of locomotion wherein an asymmetric release of surfactant by a body located at the surface of a liquid leads to its directed motion. We present in this paper a mathematical model for Marangoni propulsion in the viscous regime. We consider the case of a thin rigid circular disk placed at the surface of a viscous fluid and whose perimeter has a prescribed concentration of an insoluble surfactant, to which the rest of its surface is impenetrable. Assuming a linearized equation of state between surface tension and surfactant concentration, we derive analytically the surfactant, velocity and pressure fields in the asymptotic limit of low capillary, Péclet and Reynolds numbers. We then exploit these results to calculate the Marangoni propulsion speed of the disk. Neglecting the stress contribution from Marangoni flows is seen to over-predict the propulsion speed by 50 %.
Antioxidant and anti-inflammatory effect of conjugated linolenic acid isomers against streptozotocin-induced diabetes
Authors: Saha Siddhartha S. , Ghosh Mahua 
Published: December 2011

The present study was undertaken to evaluate the effect of α-eleostearic acid and punicic acid, two isomers of conjugated linolenic acid (CLnA) present in bitter gourd (Momordica charantia) and snake gourd oil (Trichosanthes anguina), respectively, against oxidative stress, inflammatory challenge and aberration in erythrocyte morphology due to streptozotocin (STZ)-induced diabetes. Male albino rats were divided into four groups consisting of eight animals in each group. The first group served as control and diabetes was induced in rats in groups 2–4 by a single intraperitoneal injection of STZ. Moreover, rats in groups 3 and 4 were treated with 0·5 % of α-eleostearic acid and 0·5 % of punicic acid of the total lipid given, respectively, by oral administration once per d. After administration, CLnA isomers had significantly reduced oxidative stress, lipid peroxidation and restored antioxidant and pro-inflammatory enzymes such as superoxide dismutase, catalase, and glutathione peroxidase, reduced glutathione, NO synthase level in pancreas, blood and erythrocyte lysate. The ferric reducing antioxidant power (FRAP) assay of plasma showed that CLnA treatment caused improvement in the FRAP value which was altered after STZ treatment due to an increased level of free radicals. Expression of inflammatory cytokines such as TNF-α and IL-6 in blood and expression of hepatic NF-κB (p65) increased significantly after STZ treatment due to increased inflammation which was restored with the administration of CLnA isomers. From the obtained results, it could be concluded that α-eleostearic acid and punicic acid showed potent antioxidant and anti-inflammatory activity with varying effectivity.
Pathology of enteric infections induced by the acanthocephalanProfilicollis chasmagnathiin Olrog's gull,Larus atlanticus, from Argentina
Authors: La Sala L.F. , Perez A.M. , Smits J.E. , Martorelli S.R. 
Published: December 2011

AbstractAcanthocephalans can be pathogenic helminths of marine birds. Every year during the breeding season, there is variable mortality among prefledged chicks from the largest known Olrog's gull (Larus atlanticus) colony. Mortality has been associated with infection by the acanthocephalanProfilicollis chasmagnathi. Our aim was to study the role of chicks' size as a risk factor for intensity of infection and severe pathology, and to expand upon previous pathological findings reported in acanthocephalan-infected chicks. Size of the chick was associated with intensity of infection and number of intestinal perforations, which increased by 6.9% and 4.1%, respectively, for each millimetre increment in chick size. Infection was associated with inflammatory enteritis and granulomatous peritonitis. Complete intestinal perforations were observed in 85% and 97.3% of the studied chicks in 2005 and 2006, respectively, and they were observed very early during the post-hatching period. Our results show: (1) the presence of advanced pathology associated with acanthocephalan infections in chicks, beginning very early in the post-hatching period; and (2) significant increases in the intensity of infection and the associated pathology as a function of size of chicks, in dead chicks during this period.
Bilateral fungiform papilloma with synchronous verrucous carcinoma of the nasal septum: a rare presentation and a literature review
Authors: Maithani T , Dey D , Pandey A , Chawla N 
Published: December 2011

AbstractAim:Fungiform papillomas are benign mucosal neoplasms presenting as a unilateral exophytic mass involving the anterior portion of the nasal septum. In this study, we present an exceptional case of a bilateral fungiform papilloma with a synchronous verrucous carcinoma of the nasal septum.Material and methods:A case study with a review of the literature concerning malignant changes in fungiform papilloma.Results:The general consensus in most of the literature is that malignant change in fungiform papilloma is exceptional. Our patient is probably the third reported case of verrucous carcinoma of the nasal septum, and the first report of a bilateral fungiform papilloma with a synchronous verrucous carcinoma. The tumour was subjected to complete surgical removal in the first instance. There was no recurrence at follow up seven months after surgery.Conclusion:Although fungiform papillomas are generally not premalignant, occasional malignant transformation may occur. Thus, they must be managed with the utmost cautiousness.