bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transition of chromium oxyhydroxide nanomaterials to chromium oxide: a hot‐stage Raman spectroscopic study
Authors: Yang Jing (Jeanne) , Martens Wayde N. , Frost Ray L. 
Published: August 2010

AbstractThe transition of disc‐like chromium hydroxide nanomaterials to chromium oxide nanomaterials has been studied by hot‐stage Raman spectroscopy. The structure and morphology of α‐CrO(OH) synthesised using hydrothermal treatment were confirmed by X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The Raman spectrum of α‐CrO(OH) is characterised by two intense bands at 823 and 630 cm−1 attributed to ν1 CrIIIO symmetric stretching mode and the band at 1179 cm−1 attributed to CrIIIOH δ deformation modes. No bands are observed above 3000 cm−1. The absence of characteristic OH stretching vibrations may be due to short hydrogen bonds in the α‐CrO(OH) structure. Upon thermal treatment of α‐CrO(OH), new Raman bands are observed at 599, 542, 513, 396, 344 and 304 cm−1, which are attributed to Cr2O3. This hot‐stage Raman study shows that the transition of α‐CrO(OH) to Cr2O3 occurs before 350 °C. Copyright © 2010 John Wiley & Sons, Ltd.
Temperature effects on a doubly tethered diproline chiral stationary phase: Hold‐up volume, enantioselectivity and robustness
Authors: Lao Wenjian , Gan Jay 
Published: August 2010

AbstractEffect of temperature on hold‐up volume, enantioselectivity and robustness of a novel doubly tethered diproline chiral stationary phase (CSP1) was studied. In‐column end‐capping of residual silanol was utilized as a tool to exhibit in situ change of CSP1. The hold‐up volume marker, 1,3,5‐tri‐tert‐butylbenzene, was observed to be weakly retained (<1 s ) on a 5 cm×4.6 mm chiral column, and its retention time was changed with the carrier solvent and column temperature. The apparent thermodynamic parameters of 1,3,5‐tri‐tert‐butylbenzene indicated an enthalpy‐driven retention process with the hexane/isopropanol mobile phase, while an entropy‐driven process with the hexane/methyl tert‐butyl ether mobile phase. The ΔΔH and ΔΔS values of chiral separation for the four probes including 1,1′‐bi‐2‐naphthol and warfarin were negative on CSP1. Nonlinear van't Hoff plots were observed for some analytes before and after the end‐capping treatment. Depending on compound, end‐capping strengthened or weakened the enantioseparation. Moreover, the enantioselectivity of CSP1 was shown to be robust by testing with heating–cooling cycles and step‐temperature programs.
Poly(N‐vinylimidazole)‐grafted capillary for electrophoresis prepared by surface‐initiated atom transfer radical polymerization
Authors: Li Jing , Han Haifeng , Wang Qing , Liu Xia , Jiang Shengxiang 
Published: August 2010

AbstractA CE method for poly(N‐vinylimidazole) (PVI)‐grafted capillaries by the surface‐initiated atom transfer radical polymerization has been developed. The coating was prepared with N‐vinylimidazole as the monomer, 2‐bromo‐2‐methyl‐N‐[3‐(triethoxysilyl) propyl] propanamide (BTPAm) as the initiator and CuCl/CuCl2/2,2′‐bipyridine as the catalyst and ligand. The direction and magnitude of EOF in the PVI‐grafted capillary were investigated in a pH range of 3.0–9.0. The results indicated that the EOF could be modulated by varying the pH value of the buffer and an anodic EOF was obtained at pH values below 6.5. A significant improvement in reproducibility and reduction of EOF appeared on the PVI‐grafted capillary when compared with the uncoated capillary. Furthermore, the polymer coated capillaries were applied to the separations of the inorganic anions, organic acids and basic proteins and baseline separations were achieved with short analysis time and high reproducibility.
Physical characterization and evaluation of HPLC columns packed with superficially porous particles
Authors: Baker Jared S. , Vinci John C. , Moore Amber D. , Colón Luis A. 
Published: August 2010

AbstractTwo HPLC columns packed with superficially porous packing material (Kinetex™ 1.7 and 2.6 μm C18 particles) were evaluated in terms of their physical properties and performance characteristics. These columns were compared to a column packed with a sub‐2 μm totally porous material and to a HaloTM column packed with 2.7 μm C18 superficially porous packing. The columns packed with superficially porous particles displayed a comparably narrower size distribution, which is narrower than the distribution of the totally porous sub‐2 μm particles. Physical characteristics of the Kinetex™ particles were evaluated in terms of surface area, pore diameter, and specific pore volume. Total, external, internal, and shell porosities among the four different columns were evaluated and compared. The specific permeability for the Kinetex™ columns showed values close to those predicted by the Kozeny–Carman equation. All four columns were evaluated in terms of their chromatographic performance and compared using the Knox equation. The columns packed with the 2.6 and 2.7 μm superficially porous materials showed reduced plate heights below 2, whereas the sub‐2 μm particles showed values of 2.2 and above.
Middle turbinectomy for exposure in endoscopic endonasal transsphenoidal surgery: When is it necessary?
Authors: Guthikonda Bharat , Nourbakhsh Ali , Notarianni Christina , Vannemreddy Prasad , Nanda Anil 
Published: August 2010

AbstractObjectives:To evaluate the benefits of middle turbinectomy on the exposure of the skull base structures.Design:An anatomical study on 20 fresh cadaver heads.Methods:The extent of the exposure of the skull base structures during endoscopic endonasal approach has not been addressed specifically in respect to the whether or not the middle turbinectomy is performed. We compared the extent of exposure obtained by endonasal transsphenoidal approaches without middle turbinectomy (NMT), with unilateral turbinectomy (UMT), and with bilateral turbinectomy (BMT). Our preselected target points in the skull base consisted of sella turcica, tuberculum sella, planum sphenoidale, clivus (upper and middle third), and ipsilateral sphenopalatine artery (SPA).Results:Of our preselected anatomic target points, only the middle third of the clivus and ipsilateral SPA had enhanced exposure in UMT (100% for both structures) compared to NMT (45% and 20%, respectively). The addition of a BMT did not provide added exposure to any target compared with a UMT.Conclusions:Middle turbinectomy may not be necessary for endonasal transsphenoidal approach to the lesions of the sella, planum sphenoidale, and upper third of the clivus. However, gaining access to the middle clival region is facilitated by resection of middle turbinate. Laryngoscope, 2010
Expression of mucin (MUC) genes in mucoepidermoid carcinoma
Authors: Shemirani Nima , Osipov Vladimir , Kolker Alex , Khampang Pawjai , Kerschner Joseph E. 
Published: August 2010

AbstractObjectives/Hypothesis:Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland tumor. The presence of mucin (MUC) genes has been correlated with patient prognosis using immunohistochemical techniques. This study was undertaken to 1) investigate the expression of newly discovered MUC genes in MEC specimens, 2) assess the correlation of this expression to prognosis, and 3) further investigate the correlation of previously identified MUC genes to prognosis using molecular techniques.Study Design:Retrospective chart review and sample isolation.Methods:Twenty‐three patients with a diagnosis of MEC underwent mucin gene analysis of tumor and normal surrounding salivary gland tissue. Initial expression analysis of recently identified mucin genes MUC 12, 13, 17, 18, and 19 was performed using reverse transcription‐polymerase chain reaction (RT‐PCR) followed by quantitative assessment with quantitative PCR. Additional assessments of mucin genes MUC 1 and MUC 4, which have previously been associated with MEC, were also analyzed with real‐time RT‐PCR.Results:MEC was associated with MUC 19 expression in 65% of tumor samples compared to only 26% of normal tissue (P = .02). MUC 18 demonstrated equal expression in both tumor and normal tissue. MUC 12 and 17 were not expressed in either MEC or normal salivary gland. MUC 13 was found in 13% of tumors and 0% of normal samples. MUC 1 and MUC 4 were expressed 4.2‐ and 21‐fold higher in stage I disease in tumor tissue compared to normal, respectively.Conclusions:Presence of MUC 19 is suggestive of mucoepidermoid carcinoma, and higher expression of MUC 1 and MUC 4 is correlated with earlier stage disease. Laryngoscope, 2011
Better performance with bone‐anchored hearing aid than acoustic devices in patients with severe air‐bone gap
Authors: de Wolf Maarten J. F. , Hendrix Sander , Cremers Cor W. R. J. , Snik Ad F. M. 
Published: August 2010

AbstractObjectives/Hypothesis:A study performed in the 1990s with analogue linear hearing aids showed that in patients with mixed hearing loss and an air‐bone gap that exceeded 25 to 30 dB, speech perception was better with a bone‐anchored hearing aid (Baha) than with a conventional behind‐the‐ear (BTE) device. The objective of the present study was to investigate whether this conclusion applies to today's digital BTEs with feedback cancellation and whether the crossover point still occurs at an air‐bone gap of 25 to 30 dB.Study Design:Case control.Methods:Experienced unilateral Baha users with the latest digital Baha processors were fitted with a powerful BTE with feedback cancellation. After an acclimatization period of 4 weeks, aided thresholds and speech recognition scores were determined and compared to those recorded previously with the Baha. To obtain patients' opinions, a disability‐specific questionnaire was used. Participants comprised 16 subjects with bilateral mixed hearing loss participatedResults:Audiometric and speech recognition data showed similar trends to those described previously, but the crossover point had shifted to an air‐bone gap of 30 to 35 dB. In the questionnaire, the BTE was rated higher than the Baha, except by the patients with an air‐bone gap that exceeded an average of 45 dB.Conclusions:In patients with mixed hearing loss whose air‐bone gap exceeded 35 dB, speech recognition is likely to be better with a Baha than with a BTE. Therefore, the Baha should receive greater consideration when mixed hearing loss is combined with a significant air‐bone gap, even when there are no contraindications for BTEs. Laryngoscope, 2011
Land abandonment, landscape evolution, and soil erosion in a Spanish Mediterranean mountain region: The case of Camero Viejo
Authors: Arnaez J. , Lasanta T. , Errea M. P. , Ortigosa L. 
Published: August 2010

AbstractThe Spanish Mediterranean mountains have played an important social and economic role for many centuries. However, since the 1950s these regions have been considered of little economic interest, and this has led to the abandonment of villages, reduced productive activity, and significant changes in the landscape. In the last 50 years the Camero Viejo region (Iberian System, northeast Spain) has been subject to these changes, and was selected as our study area. Landscape evolution and soil erosion, as a result of agricultural abandonment, were studied using different analysis techniques: photointerpretation, geographic information systems and rainfall simulation. The results showed that a large proportion of previously cultivated land has been subject to plant recolonization processes. From 1956 to 2001, woodlands area increased from 10·1 per cent to 37 per cent, and scrubland increased from 42 per cent to 60 per cent. Changes in landscape structure in the same period suggest that the Camero Viejo is in a transitional stage from a highly humanized landscape to a more natural landscape. Although plant cover expansion is evident on most Camero Viejo hillslopes, in some terraced areas erosion processes are active. The generalized abandonment of agricultural terraces has favored the collapse of the stone walls of the terraces, with sliding of the soil. Surface runoff on abandoned terraces is also important. These erosion processes are related to the hydrological functioning of slopes following abandonment, neglect, and in some areas the intensification of grazing. Terrace destruction has a negative impact on the landscape and represents the loss of fertile soils. Landscape diversity should be preserved as an essential element of the economic potential of the Camero Viejo. Copyright © 2010 John Wiley & Sons, Ltd.
Risk of transmission of systemic transthyretin amyloidosis after domino liver transplantation
Authors: Lladó Laura , Baliellas Carme , Casasnovas Carlos , Ferrer Isidre , Fabregat Joan , Ramos Emilio , Castellote Jose , Torras Jaume , Xiol Xavier , Rafecas Antoni 
Published: August 2010

Abstract
Recent reports of the transmission of systemic transthyretin (TTR) amyloidosis after domino liver transplantation (DLT) using grafts from patients with familial amyloid polyneuropathy (FAP) have raised concerns about the procedure. The aim of this study was to evaluate the transmission incidence of systemic TTR amyloidosis after DLT with a complete clinical, neurological, and pathological assessment. At our institution, DLT has been performed 31 times with livers from patients with FAP. Seventeen of the 19 patients still alive in 2008 agreed to enter the study. This cross-sectional study of this cohort of patients included clinical assessments, rectal biopsy, and electroneuromyography (as well as sural nerve biopsy when it was indicated). The mean follow-up at the time of the study was 62.6 ± 2.9 months. Clinically, 3 patients complained of weak dysesthesia. When a focused study was performed, 8 patients reported some kind of neurological and/or gastrointestinal disturbance. Six of the rectal biopsy samples showed amyloid deposits (TTR-positive). Electromyography (EMG) showed signs of mild sensorimotor neuropathy in 3 cases and moderate to severe sensorimotor neuropathy in 1 case. Only 2 of the 4 patients with EMG signs of polyneuropathy showed amyloid deposits in their rectal biopsy samples. Sural nerve biopsy revealed amyloid deposits (TTR-positive) in all 4 patients with EMG signs of polyneuropathy. Two patients with normal EMG findings had TTR-positive amyloid deposits in their sural nerve biopsy samples. In conclusion, de novo systemic amyloidosis after DLT may be more frequent and appear earlier than was initially thought. In our opinion, however, the graft shortage still justifies DLT in selected patients, despite the risk of de novo systemic amyloidosis. Sural nerve biopsy with EMG and clinical correlation is mandatory for confirming the disease. Indeed, other causes of neuropathy should be excluded. Liver Transpl 16:1386–1392, 2010. © 2010 AASLD.
Identification of new donor variables associated with graft survival in a single-center liver transplant cohort
Authors: Nafidi Otmane , Marleau Denis , Roy André , Bilodeau Marc 
Published: August 2010

Abstract
We currently face the more widespread use of marginal livers for organ transplantation. Therefore, it is imperative to adequately identify the factors affecting early and late graft survival in that setting. The objective of this study was to determine the donor variables associated with graft survival in the liver transplant program of the University of Montreal. We retrospectively studied the survival of 634 grafts transplanted into 634 recipients between 1990 and 2008. The variables associated with 1- and 5-year graft survival were identified with the Cox proportional hazards regression model. The donor population was characterized by a mean age of 45.24 ± 18.15 years; 52.8% had at least 1 of the currently recognized extended criteria donor factors. The recipients had a mean age of 52.51 ± 10.80 years and a mean Child-Pugh score of 9.58 ± 2.32. Liver grafts were considered inadequate with respect to their gross appearance in 16 cases (2.5%). The 1- and 5-year graft survival rates were 78.7% and 71.1%, respectively. According to a Cox regression multivariate analysis, the independent determining factors associated with graft survival were (1) the graft appearance (P < 0.001 at 1 and 5 years), (2) the donor partial pressure of oxygen/fraction of inspired oxygen ratio (P = 0.005 at 1 year and P < 0.005 at 5 years), and (3) the donor hemoglobin level (P = 0.008 at 1 year and P = 0.005 at 5 years). In conclusion, the gross graft appearance, the presence of donor lung diffusion abnormalities, and the donor hemoglobin levels were significantly associated with graft survival. These observations, if they are confirmed, could improve our ability to select marginal organs. Liver Transpl 16:1393–1399, 2010. © 2010 AASLD.
Incidental intracardiac thromboemboli during liver transplantation: Incidence, risk factors, and management
Authors: Xia Victor W. , Ho Jonathan K. , Nourmand Hamid , Wray Christopher , Busuttil Ronald W. , Steadman Randolph H. 
Published: August 2010

Abstract
Even though numerous cases of massive thromboemboli have been reported in the literature, intracardiac thromboemboli (ICTs) incidentally found during orthotopic liver transplantation (OLT) have not been examined. In this study, we retrospectively examined the incidence, risk factors, and management of incidental ICTs during OLT. After institutional review board approval, adult patients who underwent OLT between January 2004 and December 2008 at our center were reviewed. ICTs were identified and confirmed by the examination of OLT datasheets, anesthesia records, and recorded transesophageal echocardiography (TEE) clips. The clinical presentation, management, and outcomes of the patients with ICTs were reviewed. Risk factors were analyzed by multivariate logistic regression. During the study period, 426 of the 936 adult OLT patients (45.5%) underwent intraoperative TEE monitoring. Incidental ICTs were identified in 8 of these 426 patients (1.9%). Two ICTs occurred before reperfusion, and 6 ICTs occurred after reperfusion. The treatment was at the discretion of the treating physicians; however, none of the patients received an anticoagulant or thrombolytics. Multivariate analysis identified 2 independent risk factors for intraoperative incidental ICTs: the presence of symptomatic or surgically treated portal hypertension (a history of gastrointestinal bleeding, a transjugular intrahepatic portosystemic shunt procedure, or portocaval shunt surgery) before OLT and intraoperative hemodialysis (odds ratios of 4.05 and 7.29, respectively; P < 0.05 for both). In conclusion, incidental ICTs during OLT occurred at a rate of 1.9% and were associated with several preoperative and intraoperative risk factors. The use of TEE allows early identification, which may be important. Our management for incidental ICTs is described; however, no conclusions can be made about the optimal therapy. Liver Transpl 16:1421–1427, 2010. © 2010 AASLD.
Solid Peptide Nanoparticles – Structural Characterization and Quantification of Cargo Encapsulation
Authors: Dittrich Christian , Meier Wolfgang 
Published: August 2010

AbstractCD3ac, an uncharged and strongly hydrophobic 10 amino acid peptide (Ac‐LK(Ac)‐LK(Ac)‐LK(Ac)‐LW‐DL‐LW‐DL‐LW‐DL‐LW‐NH2) was synthesized and purified. The peptide readily dissolves in ethanol and – upon solvent exchange to water – assembles into solid spherical particles with diameters of around 500 nm and low size‐polydispersity. CD3ac self‐assembles in a convenient one‐step‐process in the absence of a templating two‐phase solvent system or any other templating agents. Circular dichroism reveals a gramicidin‐like secondary structure, which can be attributed to the presence of D‐leucine, whereas LCD3ac, a peptide of identical constitution yet composed entirely of L‐amino acids precipitates amorphously. The unacetylated derivative of LCD3ac (LCD3) displays α‐helical character in circular dichroism. During the process of bead formation, CD3ac can take up and enrich water‐soluble and – insoluble cargo compounds, which is exemplified by the encapsulation of rose bengal (RB) and 5‐carboxy‐fluorescein (CF), two xanthene derivatives. We confirmed their presence in CD3ac beads by confocal fluorescence microscopy and quantified the encapsulation efficiency by absorption measurements of dissolved RB‐containing peptide bead suspensions. Loaded CD3ac beads consist of up to 40 mol‐% RB, which corresponds to a logarithmic partition coefficient of 2.95. To the best of our knowledge CD3ac is the first peptide synthesized by Fmoc chemistry which forms solid particles in the nano‐ and micrometer size range and holds promise for drug delivery applications.magnified image
Equilibrium Constants and Activation Rate Coefficients for Atom Transfer Radical Polymerizations at Pressures up to 2 500 Bar
Authors: Buback Michael , Morick Joachim 
Published: August 2010

AbstractEquilibrium constants, KATRP, and activation rate coefficients, kact, have been measured up to 2 500 bar and used for estimating reaction volumes, ΔVR, and activation volumes, ΔV‡act, respectively. Quantitative analysis of binary copper‐ligand–alkyl bromide initiator systems, without monomer being present, has been carried out in a solution of acetonitrile by high‐pressure online‐FT‐NIR/VIS spectroscopic monitoring of the CuII ligand species. The numbers for ΔVR and ΔV‡act are close to each other and reflect the characteristics of ligand complexation. Whereas ΔVR is almost insensitive to the type of initiator, the absolute KATRP clearly depends on this alkyl bromide species.magnified image
Functional Dendritic Polymers for the Development of Hybrid Materials for Water Purification
Authors: Arkas Michael , Tsiourvas Dimitris , Paleos Constantinos M. 
Published: August 2010

AbstractDendritic polymers can, depending on their polarity and the interaction ability of their interior, encapsulate water contaminants. By appropriate functionalization of their external groups and following integration with ceramics, hybrid devices bearing nanosized sorbents are developed. In a first strategy, hydrophobic dendritic polymers were non‐covalently attached on the surface of ceramic filter modules, while in a second, dendritic polymers were covalently bound on these surfaces. In another method, dendritic polymers act as templates and induce the formation of silica/dendritic polymer nanospheres. In all cases, the property of dendritic polymers to encapsulate impurities remains intact, leading to effective filtration/purification systems.magnified image
Photoinduced Controlled Radical Polymerization
Authors: Tasdelen Mehmet Atilla , Uygun Mustafa , Yagci Yusuf 
Published: August 2010

AbstractWell‐controlled radical polymerization of methyl methacrylate can be achieved by in situ photochemical generation of copper (I) complex from air‐stable copper (II) species without using any reducing agent at room temperature. The living character of this polymerization was confirmed by both the linear tendency of molecular weight evolution with conversion and a chain extension experiment.magnified image