bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, Structure, and Ring‐Opening Polymerization Catalysis of Zinc Complexes Containing Amido Phosphinimine Ligands
Authors: Liang Lan‐Chang , Tsai Tzung‐Ling , Li Chun‐Wei , Hsu Yu‐Lin , Lee Ting‐Yu 
Published: May 2011

AbstractA series of amido phosphinimine ligands of the type [(NAr1)‐o‐(Ph2P=NAr2)C6H4]– (2a: Ar1 = 2,6‐C6H3iPr2, Ar2 = 2,6‐C6H3iPr2; 2b: Ar1 = 2,6‐C6H3iPr2, Ar2 = 2,4,6‐C6H2Me3; 2c: Ar1 = 2,6‐C6H3Me2, Ar2 = 2,4,6‐C6H2Me3), which are electronic variations of monoanionic β‐diketiminates, have been employed to examine the coordination chemistry of zinc. Alkane elimination reactions of ZnR2 (R = Me, Et) with H[2a–c] in toluene or ethereal solutions at –35 °C afforded cleanly the corresponding organozinc complexes [2a–c]ZnMe (3a–c) and [2a–c]ZnEt (4a–c). Deprotonation of H[2a–c] with nBuLi at –35 °C generated [2a–c]Li (5a–c), which may be isolated as either solvent‐free complexes or solvated adducts depending on the reaction solvents employed (toluene, OEt2, or THF). Metathetical reactions of 5a·OEt2 with Zn(OAc)2 in THF at –35 °C produced [2a]Zn(OAc) (6a). These amido phosphinimine derivatives all display solution Cs symmetry on the NMR timescale. The mononuclear nature of the three‐coordinate alkyls 3–4 and four‐coordinate acetate 6a was confirmed by single‐crystal X‐ray diffraction analyses. Interestingly, the alkyl complexes 3a–c and 4a–c are all active initiators for the catalytic ring‐opening polymerization of ϵ‐caprolactone, whereas the acetate 6a is comparatively inactive.
Influence of Poly(3‐octylthiophene) on the Water Transport Through Methacrylic‐Acrylic Based Polymer Membranes
Authors: Sundfors Fredrik , Höfler Lajos , Gyurcsányi Róbert E. , Lindfors Tom 
Published: May 2011

AbstractAccumulation of water in ion‐selective membranes, can lead to inconsistent potentiometric responses with solid‐contact ion‐selective electrode (SC‐ISE) formats, and hence it is essential to restrain their water uptake. We have used FTIR‐ATR spectroscopy to study how the water uptake is influenced by the intermixing of a poly(3‐octylthiophene) (POT) SC and a poly(methyl methacrylate):poly(n‐decyl methacrylate) (PMMA:PDMA) based polymeric membrane matrix, the only SC‐ISE system for which direct evidence was provided on the aqueous layer elimination. Numerical simulations of the FTIR‐ATR spectra of 1 or 5 wt% POT containing PMMA:PDMA membranes showed that the addition of 5 wt% POT to the membrane lowered the equilibrium water uptake, whereas the diffusion coefficients of water in the membrane were found to be less affected. Consequently, POT is beneficial for preventing the formation of detrimental water layers in the SC‐ISE structure.
Antipassivating Electrochemical Process of Glassy Carbon Electrode (GCE) Dedicated to the Oxidation of Nitrophenol Compounds
Authors: Pontié M. , Thouand G. , De Nardi F. , Tapsoba I. , Lherbette S. 
Published: May 2011

AbstractWe report for the first time a novel electrochemical treatment applied to a glassy carbon electrode (GCE) during p‐nitrophenol (PNP) oxidation and dedicated to the limitation of electrode passivation by nitrophenol compounds oxidation. We propose an electrochemical process of direct phenol oxidation by starting the electrolysis at a very low potential, −1.2 V/SCE, in order to generate a soluble monomer, p‐aminophenol, on the electrode surface. Then, p‐aminophenol elaborated on the electrode surface in the place of oligomers, gives benzoquinone as a by‐product and no film formation was observed. Furthermore, the presence of a p‐NiTSPc (film of nickel tetrasulfonated phtalocyanine) coating permitted to increase two times the electrode sensitivity without passivation, too.
Electrochemical oxidation of sulfide in oil wastewater using Ti/Iro2 anode
Authors: Wang Yuting , Li Miao , Feng Chuanping , Zhang Zhenya 
Published: May 2011

AbstractThe removal of sulfide from the effluent of oil wastewater containing high concentrations of chloride ions was studied with an electrochemical oxidation technique using a Ti/IrO2 anode. It was found that current density can enhance the removal of sulfide. At a current density of 25 mA/cm2, nearly 90.5% sulfide was oxidized in 10 min. At a fixed current density of 16.67 mA/cm2, a low initial concentration of sulfide (4.21 mg/L) was completely oxidized in 5 min while a high initial concentration of sulfide (50 mg/L) required 25 min for full oxidation. A synthetic solution was also used to investigate the effect of NaCl concentration, pH, and temperature on sulfide removal, and the results were discussed. NaCl concentration, acid conditions, and high temperature can all increase the removal of sulfide. The removal of sulfide was also investigated by using oxidation reduction potential (ORP). When the sulfide was completely oxidized, the ORP of the solution changed from negative (−300 to −600 mV) to positive. This study shows that, in general, the electrochemical method was effective for the removal of sulfide from oil wastewater. © 2011 American Institute of Chemical Engineers Environ Prog, 2011
Seismic behavior of bridges with pier and foundation strengthening: PsD tests and analytical study
Authors: Chotesuwan Anawat , Mutsuyoshi Hiroshi , Maki Takeshi 
Published: May 2011

SUMMARYBy means of a simplified three degrees of freedom model, seismic behavior of reinforced concrete bridge piers and foundations were evaluated based on pseudo‐dynamic (PsD) tests for cases where pier strengthening and foundation strengthening are implemented. In addition, analysis based on PsD test results was conducted to investigate the influence of pier strengthening on seismic damage to the foundation. The PsD tests and the analysis show that the foundation suffers increased hysteretic response when pier strengthening is applied. The results also show that the foundation strengthening can prevent foundation damage. Copyright © 2011 John Wiley & Sons, Ltd.
Algebraic multigrid and discrete calculus representations of coupled‐fields
Authors: Webster R. 
Published: May 2011

SUMMARYThis paper discusses the application of scalar algebraic multigrid methods to the solution of discrete approximations to coupled scalar‐vector fields. All discretizations considered are based on the direct enforcement of the conservation laws on chosen control volumes. They are distinguished by different choices for the field variables. Both local (point based) and non‐local (domain based) variables are considered; these include variables associated with volumes (cells), areas (faces), lines (edges) and points (nodes) of the computational mesh. Two algebraic multigrid (AMG) methods are applied; both are based on the scalar unknown approach of Ruge and Stueben, but distinguished by exploiting different Galerkin coarse grid approximations (CGAs). The first is the classical method (C‐AMG) in which the CGAs are based on system reduction by subset selection. The second is the method of Vanek and others, in which the CGA is based on system reduction by aggregation (SA‐AMG). Clearly, for consistent coarse‐grid approximations, the equations must be capable of being sensibly combined in the case of SA‐AMG, and that chosen subsets be sensibly representative in the case of C‐AMG. By addressing different discrete formulations of the Stokes problem, the investigation shows that some formulations, which may be convergent using single‐grid solution methods, may not be convergent when using scalar AMG solvers. This is because they do not allow the coarsening criteria mentioned earlier to be satisfied without additional explicit geometrical/topological information, that is, the equation system alone does not contain sufficient information to permit the construction of consistent CGAs. The findings remind us that, for consistent CGAs, the coarsening process should always respect both the equation type (scalar, vector, etc) and the topology of those space elements that are an integral part of the field description (oriented points, lines, areas and volumes). A more general approach to AMG seems to be required for discrete calculus applications, possibly based on the methods of algebraic topology. Copyright © 2011 John Wiley & Sons, Ltd.
Modeling low Reynolds number incompressible flows with curved boundaries using SPH
Authors: Liang C. X. , Zhang C. Y. , Liu H. Y. , Qin Z. R. , Wang Q. 
Published: May 2011

SUMMARYIn this paper, a method that can be used to model low Reynolds number incompressible flows with curved boundaries using SPH was presented. In contrast to that usually used for the flows with flat and straight boundaries, the hydrostatic pressure gradient is treated as a variable body force in this method, and thus, it can be applied to simulate the flows with curved boundaries. Three numerical examples of low Reynolds number incompressible flows, including Poiseuille flow, flow in a section of blood vessel with a local expansion, and flow between inclined plates were calculated to test the method. The results obtained with the proposed method were in good agreement with the analytical solutions. It implies that the method presented in this paper can be successfully used to simulate low Reynolds number incompressible flows not only with flat and straight boundaries but also with curved boundaries. Copyright © 2011 John Wiley & Sons, Ltd.
Diagnosis and management of parotid carcinoma with a special focus on recent advances in molecular biology
Authors: Vander Poorten Vincent , Bradley Patrick J. , Takes Robert P. , Rinaldo Alessandra , Woolgar Julia A. , Ferlito Alfio 
Published: May 2011

AbstractRecent progress in diagnosis, treatment, prognosis, and outcome of parotid cancer is reviewed. Modern imaging allows evaluation of the anatomical extent of the cancer and its relationship to the facial nerve, and the World Health Organization (WHO) Histological Classification facilitates accurate, consistent diagnosis. Surgery remains the treatment of choice with preservation of a functioning facial nerve. Resection of the facial nerve should only be undertaken when there is clinical evidence of nerve dysfunction. The NO neck should be treated in advanced‐stage and high‐grade cancers, but the choice between elective surgery and elective irradiation remains controversial. Low‐stage, low‐grade tumors can generally be cured by surgery alone. Postoperative radiotherapy improves locoregional control in all other tumor stages and grades. Currently, the diagnostic and therapeutic approach to parotid cancer offer few options for a class of neoplasms that has many subtypes each with a unique molecular background and variable clinical behavior. Nonetheless, this approach results in a satisfactory locoregional cancer control, making distant metastasis the most frequent cause for treatment failure. At present, systemic treatment for distant failure is disappointing, although recent progress in molecular biology has suggested that adding targeted therapy should achieve tumor response or stabilization. Although disease control remains variable, the prognosis of individual patients can be increasingly accurately predicted by multivariate analysis. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Addressing inpatient crowding by smoothing occupancy at children's hospitals
Authors: Fieldston Evan S. , Hall Matthew , Shah Samir S. , Hain Paul D. , Sills Marion R. , Slonim Anthony D. , Myers Angela L. , Cannon Courtney , Pati Susmita 
Published: May 2011

AbstractOBJECTIVE:To quantify the difference in weekday versus weekend occupancy, and the opportunity to smooth inpatient occupancy to reduce crowding at children's hospitals.METHODS:Daily inpatient census data for 39 freestanding, tertiary‐care children's hospitals were used to calculate occupancy and to model the impact of reducing variation in occupancy and the change in the number of patients, patient‐days, and hospitals exposed to high occupancy pre‐ and post‐smoothing. We also calculated the proportion of weekly admissions that would require different scheduling to achieve within‐week smoothing.RESULTS:Overall, hospitals' mean occupancy ranged from 70.9% to 108.1% on weekdays, and 65.7% to 94.9% on weekends. Weekday occupancy exceeded weekend occupancy with a median difference of 8.2% points. The mean post‐smoothing reduction in weekly maximum occupancy across all hospitals was 6.6% points. Through smoothing, 39,607 patients from the 39 hospitals were removed from exposure to occupancy levels >95%. To achieve within‐week smoothing, a median 2.6% of admissions would have to be scheduled on a different day of the week; this equates to a median of 7.4 patients per week (range: 2.3–14.4).CONCLUSION:Hospitals do have substantial unused capacity, and smoothing occupancy over the course of a week could be a useful strategy that hospitals can use to reduce crowding and protect patients from crowded conditions. Journal of Hospital Medicine 2011;6:466–473. © 2011 Society of Hospital Medicine
A hairy business—Periostracal hair formation in two species of helicoid snails (Gastropoda, Stylommatophora, Helicoidea)
Authors: Allgaier Christoph 
Published: May 2011

AbstractIn molluscs, the calcareous shell is covered externally by a thin organic layer, the periostracum. The periostracum of some pulmonate species is of special taxonomic interest because it bears distinct microscale architectures. Where and how these structures are formed is as yet unknown. Using histological sections through their shells, gelatin cuts, and live observations I studied the pattern by which the periostracal hair‐like projections in two helicoid land snail species are secreted and evenly arranged on the shell. The results indicate a complex mechanism: a hair is formed in the periostracal groove independently of the periostracum, after which it is attached to the edge of the shell, drawn out of the tissue, and finally swivelled to the upper side of the periostracum. Upon further growth of the periostracum, the hairs are finally fixed upright on the shell. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc.
MR perfusion‐weighted imaging may help in differentiating between nonenhancing gliomas and nonneoplastic lesions in the cervicomedullary junction
Authors: Liu Xiang , Kolar Balasubramanya , Tian Wei , Germin Barbara I. , Huang Yuqing , Hu Rui , Zhong Jianhui , Ekholm Sven 
Published: May 2011

AbstractPurpose:To evaluate the ability of dynamic susceptibility‐weighted contrast‐enhanced magnetic resonance (MR) perfusion imaging (DSC‐PWI) in distinguishing between nonenhancing gliomas and nonenhancing, nonneoplastic lesions in the cervicomedullary junction region.Materials and Methods:This retrospective study involved eight patients with nonenhancing gliomas in the medulla oblongata and eight patients with nonenhancing nonneoplastic lesions. The relative cerebral blood volume (rCBV) ratios, peak heights, and percentage of signal intensity recovery derived from time‐signal intensity curves of these nonenhancing lesions were compared.Results:The mean peak height of nonenhancing gliomas was significantly higher than the value of their reference regions of interest (ROIs). In contrast, mean peak height of nonneoplastic lesions was significantly lower than their reference ROIs. The mean peak height and mean maximal rCBV ratio of nonenhancing gliomas were significantly higher than those of nonenhancing, nonneoplastic lesions (P<0.05). There was no significant difference with regard to percentage of signal intensity recovery between the two groups.Conclusion:DSC‐PWI could be a useful adjuvant tool to differentiate between nonenhancing gliomas and nonenhancing, nonneoplastic lesions in the cervicomedullary junction region. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Comparison of a 32‐channel with a 12‐channel head coil: Are there relevant improvements for functional imaging?
Authors: Kaza Evangelia , Klose Uwe , Lotze Martin 
Published: May 2011

AbstractPurpose:To evaluate the suitability of a 12‐ or 32‐channel head coil and of a prescan normalization filter for functional magnetic resonance imaging (fMRI) studies at different brain regions.Materials and Methods:fMRI was obtained from 36 volunteers executing a visually instructed motor paradigm using a 12‐channel head matrix coil and a 32‐channel phased‐array head coil with and without prescan normalization filtering at 3 T. The time‐course signal‐to‐noise ratio (tSNR) and the magnitude of functional activation (beta‐value, t‐value, percent signal change) were statistically compared between experimental conditions for the contralateral primary motor and visual cortex, contralateral thalamus, and ipsilateral anterior cerebellar hemispheres.Results:tSNR was higher overall measuring with the 32‐channel array and with prescan normalization. Without filtering, the 32‐channel array delivered higher functional activation magnitudes for the visual cortex, whereas the 12‐channel array seemed superior in this respect in thalamus and cerebellum. Filtering did not considerably affect the fMRI‐activation magnitude detected from the 12‐channel coil; its application favored the 32‐channel coil at the subcortical and cerebellar locations but disfavored it at the cortical ones.Conclusion:The 32‐channel coil detected more fMRI‐activation cortically but less subcortically than the 12‐channel coil; prescan normalization improved activation parameters only at central brain structures. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Mechanisms of collagen fibril alignment in tendon injury: From tendon regeneration to artificial tendon
Authors: Torigoe Kojun , Tanaka Hirohito F. , Yonenaga Kazumichi , Ohkochi Hiroki , Miyasaka Muneo , Sato Ryota , Kuzumaki Toru , Yoshida Kazuharu , Yoshida Toshiko 
Published: May 2011

AbstractThe process by which collagen fibrils are aligned following tendon injury remains unknown. Therefore, we analyzed the process of tendon regeneration by transmission electron microscopy, using a film model method. In mice, the Achilles tendon of medial head was transected. On day 3, after only the proximal end of the transected tendon was placed on film and kept in vivo, a translucent substance containing granules, called tendon gel, was secreted. On day 5, the granules assembled in a loose (L) layer, and coalesced tightly in a dense (D) layer, forming an L‐D‐L layered pattern. On day 10, granules showed high electron density in H layers, which developed into D‐H‐D layers on day 13. The distal end was placed on film to face the proximal end. On day 10, the tendon gel showed a D‐H‐D layer pattern. On day 11, mechanical stress from muscular constriction changed the tendon gel to aligned collagen fibrils (6 ± 2 nm in diameter). Thereafter, the diameter of the fibrils increased. Tendon gel harvested on day 5 or day 10 was pulled manually or by hanging weights (about 0.6 MPa). Aligned collagen fibrils (32 ± 7 nm in diameter) were created by traction using tendon gel harvested on day 10. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1944–1950, 2011
Standardized pretreatment breast MRI—accuracy and influence on mastectomy decisions
Authors: Barchie Matthew F , Clive Kevin S , Tyler Joshua A , Sutcliffe Joseph B , Kirkpatrick Aaron D , Bell Lisa M , Banks Kevin P , Belenkiy Slava , Saenger Jeff S , Peoples George E 
Published: May 2011

AbstractBackground and ObjectivesRoutine pretreatment breast magnetic resonance imaging in newly diagnosed cancer patients remains controversial. We assess MRI accuracy and influence on mastectomy decisions after institution of standardized pretreatment MRI.MethodsA prospectively collected database of 74 consecutive new invasive breast cancer patients with pretreatment breast MRI was reviewed for treatment choice, radiologic, and pathologic results. Thirty‐eight of 72 patients with available surgical records underwent mastectomy. Mastectomy preoperative and operative electronic records were reviewed for treatment decision analysis.ResultsSeventeen of 72 (23.6%) invasive breast cancer patients were likely influenced to undergo mastectomy by new information from MRI. MRI reported that the multifocal/multicentric (MF/MC) rate was 20 of 72 (27.8%) versus 19 of 72 (26.4%) by surgical pathology. MRI sensitivity for MF/MC disease was 89.5% versus 11.8% for mammography. MRI specificity was 84.2%. All three false positives declined recommended preoperative biopsies. MRI MF/MC diagnosis highly correlated with pathology results, P < 0.001.ConclusionsIncreased mastectomy rate from 29 to 52.8% after standardization of pre‐treatment breast MRI for invasive cancer is largely due to MRI findings of increased extent of disease. These MRI findings correlate well with pathologic findings and appear to justify the performance of mastectomies in these patients. J. Surg. Oncol. 2011; 104:741–745. © 2011 Wiley Periodicals, Inc.
Elevated preoperative neutrophil to lymphocyte ratio predicts poor survival following resection in late stage gastric cancer
Authors: Jung Mi Ran , Park Young Kyu , Jeong Oh , Seon Jang Won , Ryu Seong Yeob , Kim Dong Yi , Kim Young Jin 
Published: May 2011

AbstractBackgroundElevated neutrophil to lymphocyte ratio (N/L ratio) has been shown to be a prognostic indicator in various cancers. We aimed to investigate the prognostic significance of the preoperative N/L ratio in late stage gastric cancer.MethodsFrom April 2004 to August 2007, 293 patients who had undergone gastrectomy with curative intent for the AJCC/UICC TNM Stage III or IV gastric cancer were included. N/L ratio was calculated from lymphocyte and neutrophil counts on routine blood tests taken prior to surgery.ResultsThe median follow‐up time for surviving patients was 38.2 months (4.2–65.5 months) and median preoperative N/L ratio was 2.06 (range 0.47–19.73). Subjects were dichotomized at the N/L value of 2.0. A multivariate analysis established a significant relationship between the N/L ratio and overall survival (HR = 1.609; 95% confidence interval, CI, 1.144–2.264; P = 0.006). The cutoff value up to 3.0, the value of 75 percentiles, showed a significant prognostic effect on disease‐free survival (HR = 1.654; 95% CI, 1.088–2.515; P = 0.019).ConclusionsThe results suggest that the elevated preoperative N/L ratio predicts poor disease‐free and overall survival following resection for late stage gastric cancer. It may be utilized as a simple, reliable prognostic factor for risk stratification and will provide better treatment allocation. J. Surg. Oncol. 2011; 104:504–510. © 2011 Wiley‐Liss, Inc.
Relationships between soldiers' PTSD symptoms and spousal communication during deployment
Authors: Carter Sarah , Loew Benjamin , Allen Elizabeth , Stanley Scott , Rhoades Galena , Markman Howard 
Published: May 2011

AbstractSocial support, including support from spouses, may buffer against posttraumatic stress disorder (PTSD) symptoms. The current study assessed whether the frequency of spousal communication during a recent deployment, a potentially important source of support for soldiers, was related to postdeployment PTSD symptoms. Data came from 193 married male Army soldiers who returned from military deployment within the past year. For communication modalities conceptualized as delayed (i.e., letters, care packages, and e‐mails), greater spousal communication frequency during deployment was associated with lower postdeployment PTSD symptom scores, but only at higher levels of marital satisfaction (p = .009). At lower marital satisfaction, more delayed spousal communication during deployment was associated with more PTSD symptoms (p = .042). For communication modalities conceptualized as interactive (i.e., phone calls, instant messaging, instant messaging with video), the same general direction of effects was seen, but the interaction between communication frequency and marital satisfaction predicting PTSD symptoms did not reach significance.